Ch.3 - Chemical ReactionsSee all chapters
All Chapters
Ch.1 - Intro to General Chemistry
Ch.2 - Atoms & Elements
Ch.3 - Chemical Reactions
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Ch.4 - Chemical Quantities & Aqueous Reactions
Ch.5 - Gases
Ch.6 - Thermochemistry
Ch.7 - Quantum Mechanics
Ch.8 - Periodic Properties of the Elements
Ch.9 - Bonding & Molecular Structure
Ch.10 - Molecular Shapes & Valence Bond Theory
Ch.11 - Liquids, Solids & Intermolecular Forces
Ch.12 - Solutions
Ch.13 - Chemical Kinetics
Ch.14 - Chemical Equilibrium
Ch.15 - Acid and Base Equilibrium
Ch.16 - Aqueous Equilibrium
Ch. 17 - Chemical Thermodynamics
Ch.18 - Electrochemistry
Ch.19 - Nuclear Chemistry
Ch.20 - Organic Chemistry
Ch.22 - Chemistry of the Nonmetals
Ch.23 - Transition Metals and Coordination Compounds
Jules Bruno

The empirical formula represents the simplest whole numbered ratio of atoms in a compound, while the molecular formula or chemical formula represents the actual ratio of atoms in a compound. 

How do you determine the empirical formula? 

Questions usually begin with the percent compositions of elements to help find the empirical formula for ionic compounds or covalent compounds. 

For example: 

"A compound is composed of 63.81% carbon, 6.42% hydrogen, and 29.77% nitrogen by mass. Determine the empirical formula of this compound." 

STEP 1: Whenever percentages are given we assume that they are out of 100 grams of compound. This allows us to automatically change percentages into grams. 

Percentage-massPercentages to grams conversion

STEP 2: Convert the grams of each element into moles. 

Grams-to-moles-conversionGrams to moles conversion

To avoid potential rounding errors, make sure you keep at least 3 decimal places for your answers in moles. 

STEP 3: Divide all your mole answers by the smallest mole value calculated. Once you’ve divided all the moles by the smallest mole value you should obtain whole numbers.

Ratio-atomic-symbolsRatio of Atomic Symbols

STEP 4: From division we have 2.5 carbons. This step only occurs when you don’t obtain whole numbers for each element. 

We can only round if your value is X.1 or X.9. For example, if you had 2.1 carbons you could round down to 2 carbons. To obtain whole numbers we must multiply all the previous values by the same integer. 

Determining-Whole-NumbersDetermining Whole Numbers

STEP 5: With whole numbers representing subscripts for each element we can now obtain the empirical formula. 

Empirical-Formula-Superscript-SubscriptEmpirical Formula

At this point we have our empirical formula. The additional step that follows is used when we are asked to determine the molecular formula. 

STEP 6: For example: 

"If the molar mass of the compound is 188.2 g/mol, what would be the molecular formula of the compound?"

To calculate the molecular formula we use the ratio below: 

Molecular-Empirical-RatioMolecular Mass to Empirical Mass Ratio

The molecular mass or molar mass of the compound is traditionally given within the question, while the empirical mass is calculated from the empirical formula. 

Calculating-Molecular-Empirical-Ratio

Calculating Molecular Mass to Empirical Mass Ratio

Plugging in the molecular mass and empirical mass into the ratio will provide us with a whole number integer. To determine the molecular formula you will multiply the empirical formula by that integer. Molecular-FormulaMolecular Formula

Beyond calculating the empirical and molecular formulas you can also deal with steps involving combustion analysis


Jules Bruno

Jules felt a void in his life after his English degree from Duke, so he started tutoring in 2007 and got a B.S. in Chemistry from FIU. He’s exceptionally skilled at making concepts dead simple and helping students in covalent bonds of knowledge.


Additional Problems
Dichlorobenzene contains 49.02 mass % C, 2.74 mass % H, and the remainder is Cl. Determine its empirical formula. A. C3H3Cl2 B. CHCl C. C2H2Cl2 D. C3H2Cl E. C3H3Cl2
What is the empirical formula for the substance with the following analysis? Na          34.9% B            16.4% O            48.6% A. Na3BO3 B. NaBO2 C. Na4BO4 D. Na3B2O2
If the molar mass of hydrazine is 32 g/mol and its empirical formula is NH2, the molecular formula is A. NH3 B. N2H4 C. NH2 D. N4H8 E. N2H2
Give the molecular formula of the compound pictured below. A. CH B. C2H2 C. C6H6 D. C2H3
What is the empirical formula of diphosphorus tetrafluoride? 1. PF3            2. PF2            3. P2F2            4. P2F4
Determine the empirical formula of natural rubber which is 88.1% C and 11.9% H. a) C2H3 b) C3H7 c) C2H5 d) C3H5 e) C5H8
How many of the following formulas are empirical formulas? Hg2(NO3)2      H2SO4             P4O10              C2­H4O           A) 0                       B) 1                 C) 2                 D) 3                 E) 4       
What is the empirical formula for C 4H10O2? A) C2H5O  B) CHO C) CHO2 D) CH2O E) C2H4O
Methylparaben is used in food and drugs and especially in beauty products although some studies have shown that it can disrupt endocrine production. A sample of methylparaben was decomposed to its elements – carbon, hydrogen and oxygen. The percentage of hydrogen was measured to be 5.26% and that a carbon was found to be 63.2%. An error was made in attempting to determine the percentage that was oxygen so this value was not reported. What is the empirical formula of methyparaben?   a. C8H8O3 b. C6H6O c. C2H6O d. CH2O e. CHO
Determine the empirical formula for a compound that contains C, H, and O. It contains 52.14% C and 34.73% O by mass.  
Which one of the following is not an empirical formula? A) CH2O B) CHO C) C2H4O D) C2H4O2
An unknown compound was isolated, purified, and sent off for elemental analysis. It was suspected that the compound was a hydrocarbon of some type, so a carbon-hydrogen analysis was requested, and the following results were returned: %C, 59.94; %H, 12.08. A reasonable empirical formula was obtained by assuming that the remaining mass was due entirely to nitrogen, but the compound was never resubmitted for a nitrogen analysis.   a) Determine the empirical formula for the compound assuming that it consists of carbon, hydrogen, and nitrogen. Be sure to show your work, and write the empirical formula in the box provided.       The empirical formula is b) It was later determined that the other element in the compound was silicon, not nitrogen. You could repeat the above analysis based on carbon, hydrogen, and silicon, but a quick glance at the periodic table should allow you to immediately write the empirical formula based on the work you did in Part A. 1. What is the empirical formula for the compound assuming that it consists of carbon, hydrogen, and silicon? 2. Explain how you can determine the empirical formula based on the work you did in Part A without repeating the full calculation.
What is the empirical formula for ethyl fluoride if the compound contains 49.97% carbon, 10.51% hydrogen, and 39.52% fluorine by mass? A) C4H10F4 B) C2H5F C) C25F2 D) C4H10F2
A sample contains 43.7% phosphorus and 56.3% oxygen. The molar mass is 284 g. What is the molecular formula of the compound? A) P4O5 B) P4O10 C) P5O8 D) PO3 E) P2O5
What is the empirical formula for perfluoropropane if the compound contains 81% fluorine and 19% carbon by mass? A) C19F81 B) C2F8 C) C3F8 D) CF3
Glucuronolactone is found in many plant gums and is added to some energy drinks.  A sample of this compound is analyzed and it is found to consist of the following mass percentages:  40.91 percent carbon, 4.58 percent hydrogen, and 54.51 percent oxygen.     What is the empirical formula of this compound?
What is the empirical formula of a substance that contains 2.64 g of C, 0.444 g of H, and 3.52 g of O? A) CH2O B) C2H4O3 C) C2H4O2 D) C3H4O4
A compound responsible for the odor of garlic has a molecular weight of 146 g/mol. A 0.650 g sample of the compound contains 0.321 g of carbon, 0.044 g of hydrogen, and 0.285 g of sulfur. What is the molecular formula of the compound? A) C6H10S2 B) C3H15S3 C) CH5S D) C3H5S
An organic compound contains C, H, and O. The percentages of H and C are 6.73% H, and 39.99% C by mass. The molar mass is 60.06 amu. What is the molecular formula of the compound? A) CH2O B) C4H8O4 C) C2H3O2 D) C2H4O2 E) C3H6O3
Part A: A chemist attempted to synthesize a particular compound that showed promise as a new antibiotic. If she succeeded in making and purifying the compound, then it contains only carbon, hydrogen, bromine, and oxygen. She sent a sample off for analysis, and days later the following results arrived: carbon, 34.35%; hydrogen, 1.725%; bromine, 45.65%; oxygen, 18.27%   Determine the empirical formula.               Part B: Because the scientist knows the compound she is trying to make, she can calculate the molar mass, assuming she synthesized the right compound. The expected molar mass is 699.9 g/mol.  What is the molecular formula of the compound?
A molecule is found to contain 47.35% by mass C, 10.60% by mass H, and 42.05% by mass O. What is the empirical formula for this molecule? a. C2H6O b. C3H4O c. C3H8O2 d. C4H6O2 e. C4H8O3  
Determine the empirical formula for a compound that contains C, H and O. It contains 52.14% C and 34.73% O by mass. A) CHO B) CH3O C) CH4O3 D) C4H13O2 E) C2H6O
The molar mass of caffeine is 194.2 g/mol. Its empirical formula is C4H5N2O. What is its chemical formula?
Determine the empirical formula for a compound that is found to contain 10.15 mg P and 34.85 mg Cl. A) P2Cl3 B) P3Cl C) PCl3 D) PCl E) PCl2
Determine the empirical formula for a compound that is 36.86% N and 63.14% O by mass. A) NO2 B) N2O3 C) N2O D) NO E) NO3
Catechol is 65.4% carbon, 5.49% hydrogen, and 29.1% oxygen by mass. What is the empirical formula for catechol? (A) C3H3O (B) C3H3O2 (C) C6H6O2 (D) CHO0.333 (E) None of the above
Equilin is an estrogen that is commonly used in hormone replacement therapy. A sample of equilin is sent for elemental analysis and is determined to contain 80.546% carbon, 7.510% hydrogen, and 11.943% oxygen. If the molar mass of equilin is 268.34 g/mol, what is the molecular formula for equilin? a. C20H20O2 b. C18H20O2 c. C9H20O d. C27H30O3
A 4.08 g sample of a compound of nitrogen and oxygen contains 3.02 g of oxygen. What is the empirical formula? A. NO B. NO2 C. N2O D. N2O5
A compound is found to consist of 34.9% sodium, 16.4% boron and 48.6% oxygen. What is its simplest formula? a) NaBO2 b) NaBO3 c) Na2B4O7 d) Na3BO3
Upon analysis, a compound is found to contain 22.8% sodium, 21.8% boron, and 55.4% oxygen. What is its simplest formula? a) NaBO b) NaB2O5 c) Na2B4O7 d) Na3BO4
A 4.08 g sample of a compound of nitrogen and oxygen contains 3.02 g of oxygen. What is the empirical formula? a) NO b) NO2 c) N2O d) N2O5
A compound is composed of 63.81 % C, 6.42 % H, and 29.77 % N by mass. You may round element molar mass to 2 decimal places. a) The Empirical formula of this compound is ___.       b) If the molar mass of the compound in a) is 188.2 g/mol, the molecular formula of this compound is ___.
A compound with a composition of 87.5% N and 12.5% H was recently discovered. What is the empirical formula for this compound? A) NH2 B) N2H3 C) NH D) NH3 E) N2H
Which pair of the following compounds does  NOT have the same empirical formula? A) C2H5COOCH3, CH3CHO B) C2H2, C6H6 C) C2H4, C3H6 D) C2H4O2, C6H12O6 E) CO, CO2
A compound with a composition of 87.5% N and 12.5% H was recently discovered. What is the empirical formula for this compound?  A) NH2 B) N2H3 C) NH D) NH3 E) N2H
A pure sample of a new chemical compound was analyzed and was found to have the following mass percentages: Al 31.5%; O 56.1%; S 12.4%. What is the empirical formula of this compound? A) Al5O28S7 B) Al3O9S C) AlO2S2 D) Al4O14S7 E) AlO6S1.5
Determine the molecular formula of a compound that has molar mass of 183.2 g/mol and an empirical formula of C2H5O2. a. C2H5O2 b. C6H15O6 c. C3H7O3 d. C4H10O4 e. C8H20O8
Butyric acid has an unpleasant odor and is found in milk, cheese, butter. It causes the main distinctive smell in human vomit. A sample of butyric acid is sent for elemental analysis and is determined to contain 54.52% carbon, 9.151% hydrogen and 36.32% oxygen. What is the empirical formula for butyric acid? a. C5H9O3 b. C4H9O2 c C9H10O d. C2H4O Considering your response to the previous question, and knowing the molar mass of butyric acid is 88.11 g/mol, what is the molecular formula for butyric acid? a. C10H18O6 b. C4H8O2 c. C3H4O3 d. C5H12O
What is the empirical formula for this structure?
What is the empirical formula of molecule A below? a. C4H10O4 b. C2H5O2 c. C4H10O2 d. C2H4O e. C2H5O
Peroxyacylnitrate (PAN) is one of the components of smog. It is a compound of C, H, N, and O. Determine the percent composition of oxygen and the empirical formula from the following percent composition by mass: 19.8 percent C, 2.50 percent H, 11.6 percent N. What is its molecular formula given that its molar mass is about 120 g?
Consider the following four formulas: SO2, B2H6, CO, C4H2O2.Which of these formulas could be only an empirical formula, only a molecular formula, either a molecular or an empirical formula?
What is the empirical formula of the compound formed between W6+ and O2-–?
What is the empirical formula for manganese(II) oxide?
The structural formulas of the compounds n-butane and isobutane are shown below. Determine the empirical formula of each.
The structural formulas of the compounds n-butane and isobutane are shown below. Which formulas-empirical, molecular, or structural-allow you determine these are different compounds?
Write the empirical formula corresponding to each of the following molecular formulas.Al2 Br6,
Write the empirical formula corresponding to each of the following molecular formulas.C8 H10,
Write the empirical formula corresponding to each of the following molecular formulas.C4 H8 O2,
Write the empirical formula corresponding to each of the following molecular formulas.P4 O10,
Write the empirical formula corresponding to each of the following molecular formulas.C6 H4 Cl2,
Write the empirical formula corresponding to each of the following molecular formulas.B3 N3 H6.
Determine the molecular and empirical formulas of the following. You may want to reference(Pages 60 - 64)Section 2.7 while completing this problem.The organic solvent benzene, which has six carbon atoms and six hydrogen atoms
Determine the molecular and empirical formulas of the following. You may want to reference(Pages 60 - 64)Section 2.7 while completing this problem.The compound silicon tetrachloride, which has a silicon atom and four chlorine atoms and is used in the manufacture of computer chips
You may want to reference (Page 91) Section 3.3 while completing this problem.What is the empirical formula of a compound with the molecular formula C10H8?
Determine the molecular and empirical formulas of the following. You may want to reference(Pages 60 - 64)Section 2.7 while completing this problem.The reactive substance diborane, which has two boron atoms and six hydrogen atoms
Determine the molecular and empirical formulas of the following. You may want to reference(Pages 60 - 64)Section 2.7 while completing this problem.The sugar called glucose, which has 6 carbon atoms, 12 hydrogen atoms, and 6 oxygen atoms
What are the molecular and empirical formulas for each of the following compounds?Write the molecular formula for the following compound.
What are the molecular and empirical formulas for each of the following compounds?Write the empirical formula for the following compound.
What are the molecular and empirical formulas for each of the following compounds?Write the molecular formula for the following compound.
What are the molecular and empirical formulas for each of the following compounds?Write the empirical formula for the following compound.
What are the molecular and empirical formulas for each of the following compounds?Write the molecular formula for the following compound.
What are the molecular and empirical formulas for each of the following compounds?Write the empirical formula for the following compound.
Two substances have the same molecular and empirical formulas.Does this mean that they must be the same compound?
Cyclopropane is an interesting hydrocarbon. Instead of having three carbons in a row, the three carbons form a ring, as shown in this perspective drawing (see the figure for a prior example of this kind of drawing): Cyclopropane was at one time used as an anesthetic, but its use was discontinued, in part because it is highly inflammable. What is the empirical formula of cyclopropane?
Could the empirical formula determined from chemical analysis be used to tell the difference between acetylene, C2H2, and benzene, C6H6?
The organic molecules shown beloware derivatives of benzene in which additional six-membered rings are "fused" at the edges of the hexagons. The compounds are shown in the usual abbreviated method for organic molecules.Determine the empirical formula of benzene.
The organic molecules shown beloware derivatives of benzene in which additional six-membered rings are "fused" at the edges of the hexagons. The compounds are shown in the usual abbreviated method for organic molecules.Determine the empirical formula of napthalene.
The organic molecules shown beloware derivatives of benzene in which additional six-membered rings are "fused" at the edges of the hexagons. The compounds are shown in the usual abbreviated method for organic molecules.Determine the empirical formula of anthracene.
The organic molecules shown beloware derivatives of benzene in which additional six-membered rings are "fused" at the edges of the hexagons. The compounds are shown in the usual abbreviated method for organic molecules.Determine the empirical formula of tetracene.
Serotonin is a compound that conducts nerve impulses in the brain. It contains 68.2 mass percent C, 6.86 mass percent H, 15.9 mass percent N, and 9.08 mass percent O. Its molar mass is 176 g/mol.Determine its molecular formula.
The koala dines exclusively on eucalyptus leaves. Its digestive system detoxifies the eucalyptus oil, a poison to other animals. The chief constituent in eucalyptus oil is a substance called eucalyptol, which contains 77.87% C, 11.76% H, and the remainder O.A mass spectrum of eucalyptol shows a peak at about 154 amu. What is the molecular formula of the substance?
Fructose is a common sugar found in fruit. Elemental analysis of fructose gave the following mass percent composition: C 40.00%, H 6.72%, O 53.28%. The molar mass of fructose is 180.16 g/mol.Find the molecular formula of fructose.
Combustion analysis of a 13.42-g sample of equilin (which contains only carbon, hydrogen, and oxygen) produced 39.61 g CO2 and 9.01 g H2 O. The molar mass of equilin is 268.34 g/mol .Find the molecular formula for equilin.
From the given empirical formula and molar mass, find the molecular formula of each compound.C6H7N, 186.27 g/mol
From the given empirical formula and molar mass, find the molecular formula of each compound.C2HCl, 120.96 g/mol
From the given empirical formula and molar mass, find the molecular formula of each compound.C5H10NS2, 296.56 g/mol
From the given molar mass and empirical formula of several compounds, find the molecular formula of each compound. You may want to reference (Pages 116 - 119) Section 3.10 while completing this problem.C4H9, 114.22 g/mol
From the given molar mass and empirical formula of several compounds, find the molecular formula of each compound. You may want to reference (Pages 116 - 119) Section 3.10 while completing this problem.CCl, 189.85 g/mol
From the given molar mass and empirical formula of several compounds, find the molecular formula of each compound. You may want to reference (Pages 116 - 119) Section 3.10 while completing this problem. C3 H2 N, 104.13 g/mol
An elemental analysis of the acid indicates that it is composed of 5.89% H, 70.6% C, and 23.5% O by mass. What is its molecular formula?
A compound has the empirical formula CH2O and a formula mass of 120.10 amu. You may want to reference (Page 116) Section 3.10 while completing this problem.What is the molecular formula of the compound?
Estradiol is a female sexual hormone that causes maturation and maintenance of the female reproductive system. Elemental analysis of estradiol gave the following mass percent composition: C 79.37%, H 8.88%, O 11.75%. The molar mass of estradiol is 272.37 g/mol.Find the molecular formula of estradiol.
A compound of molar mass 177 g/mol contains only carbon, hydrogen, bromine, and oxygen. Analysis reveals that the compound contains 8 times as much carbon as hydrogen by mass.Find the molecular formula.
You may want to reference (Pages 98 - 102)Section 3.5 while completing this problem.Cyclohexane, a commonly used organic solvent, is 85.6% C and 14.4% H by mass with a molar mass of 84.2 g/mol. What is its molecular formula?
A compound of molar mass 229 g/mol contains only carbon, hydrogen, iodine, and sulfur. Analysis shows that a sample of the compound contains 6 times as much carbon as hydrogen, by mass.Calculate the molecular formula of the compound.
You may want to reference (Pages 116 - 119) Section 3.10 while completing this problem.A compound has the empirical formula CH and a molar mass of 78.11 g/mol . Find its molecular formula.
A compound composed of 2.1% H, 29.8% N, and 68.1% O has a molar mass of approximately 50 g/mol.What is the molecular formula of the compound?
Determine the empirical and molecular formulas of each of the following substances.Styrene, a compound substance used to make Styrofoam® cups and insulation, contains 92.3% C and 7.7% H by mass and has a molar mass of 104 g/mol.
Determine the empirical and molecular formulas of each of the following substances.Caffeine, a stimulant found in coffee, contains 49.5% C, 5.15% H, 28.9% N, and 16.5% O by mass and has a molar mass of 195 g/mol.
Determine the empirical and molecular formulas of each of the following substances.Monosodium glutamate (MSG), a flavor enhancer in certain foods, contains 35.51% C, 4.77% H, 37.85% O, 8.29% N, and 13.60% Na, and has a molar mass of 169 g/mol.
A compound isolated from the rind of lemons is found to be 88.14 % carbon and 11.86 % hydrogen by mass.The molar mass is determined to be 136.26 g/mol. What is the molecular formula?
An herbicide is found to contain only C, H, N, and Cl. The complete combustion of a 100.0-mg sample of the herbicide in excess oxygen produces 83.16 mL of CO2 and 73.30 mL of H2O vapor at STP. A separate analysis shows that the sample also contains 16.44 mg of Cl.What other information would you need to know about this compound to calculate its true molecular formula?
Determine the empirical and molecular formulas of each of the following substances. For example, butane has an empirical formula of C2H5 (lowest whole-number ratio) and a molecular formula of C4H10, where the molecular formula corresponds to the molar mass of 58.12 g/mol. You may want to reference (Pages 98 - 102)Section 3.5 while completing this problem.Ibuprofen, a headache remedy, contains 75.69%  C, 8.80%  H, and 15.51%  O by mass and has a molar mass of 206 g/mol.
Determine the empirical and molecular formulas of each of the following substances. For example, butane has an empirical formula of C2H5 (lowest whole-number ratio) and a molecular formula of C4H10, where the molecular formula corresponds to the molar mass of 58.12 g/mol. You may want to reference (Pages 98 - 102)Section 3.5 while completing this problem.Cadaverine, a foul-smelling substance produced by the action of bacteria on meat, contains 58.55%  C, 13.81%  H, and 27.40%  N by mass; its molar mass is 102.2 g/mol.
Determine the empirical and molecular formulas of each of the following substances. For example, butane has an empirical formula of C2H5 (lowest whole-number ratio) and a molecular formula of C4H10, where the molecular formula corresponds to the molar mass of 58.12 g/mol. You may want to reference (Pages 98 - 102)Section 3.5 while completing this problem.Epinephrine (adrenaline), a hormone secreted into the bloodstream in times of danger or stress, contains 59.0%  C, 7.1%  H, 26.2%  O, and 7.7%  N by mass; its molar mass is about 180 amu.
What is the molecular formula of each of the following compounds?empirical formula CH2, molar mass = 28.0 g/mol
What is the molecular formula of each of the following compounds?empirical formula NH2Cl, molar mass = 51.5 g/mol
A 0.72 mg sample of nitrogen reacts with chlorine to form 6.186 mg of the chloride.What is the empirical formula of the nitrogen chloride?
A 44.4 mg sample of phosphorus reacts with selenium to form 129 mg of the compound.What is the empirical formula of the phosphorus selenide?
A chemist decomposes samples of several compounds; the masses of their constituent elements are listed. Calculate the empirical formula for each compound.1.651 g Ag, 0.1224 g O
A chemist decomposes samples of several compounds; the masses of their constituent elements are listed. Calculate the empirical formula for each compound.0.672 g Co, 0.569 g As, 0.486 g O
A chemist decomposes samples of several compounds; the masses of their constituent elements are listed. Calculate the empirical formula for each compound.1.443 g Se, 5.841 g Br
Three pure compounds are formed when 1.00-g samples of element X combine with, respectively, 0.472 g, 0.315 g , and 0.944 g of element Z. The first compound has the formula X2 Z3.Find the empirical formula of the second compound.
Three pure compounds are formed when 1.00-g samples of element X combine with, respectively, 0.472 g, 0.315 g , and 0.944 g of element Z. The first compound has the formula X2 Z3.Find the empirical formula of the third compound.
A chemist decomposes samples of several compounds; the masses of their constituent elements are listed. Calculate the empirical formula for each compound. You may want to reference (Pages 115 - 116) Section 3.10 while completing this problem.1.245 g Ni, 5.381 g I
A chemist decomposes samples of several compounds; the masses of their constituent elements are listed. Calculate the empirical formula for each compound. You may want to reference (Pages 115 - 116) Section 3.10 while completing this problem.2.677 g Ba, 3.115 g Br
A chemist decomposes samples of several compounds; the masses of their constituent elements are listed. Calculate the empirical formula for each compound. You may want to reference (Pages 115 - 116) Section 3.10 while completing this problem.2.128 g Be, 7.557 g S, 15.107 g O
You may want to reference (Pages 116 - 119) Section 3.10 while completing this problem.A sample of a compound is decomposed in the laboratory and produces 165 g carbon, 27.8 g hydrogen, and 220.2 g oxygen. Calculate the empirical formula of the compound.
Give the empirical formula of the following compound if a sample contains 0.0130 mol C, 0.0390 mol H, and 0.0065 mol O.
Give the empirical formula of the following compound if a sample contains 11.66 g iron and 5.01 g oxygen.
You may want to reference (Pages 99 - 102) Section 3.5 while completing this problem.Determine the empirical formula of the following compound if a sample contains 0.104 mol K, 0.052 mol C, and 0.156 mol O.
You may want to reference (Pages 99 - 102) Section 3.5 while completing this problem.Determine the empirical formula of the following compound if a sample contains 5.28 g Sn and 3.37 g F.
You may want to reference (Pages 98 - 102)Section 3.5 while completing this problem.A 2.144-g sample of phosgene, a compound used as a chemical warfare agent during World War I, contains 0.260 g of carbon, 0.347 g of oxygen, and 1.537 g of chlorine. What is the empirical formula of this substance?
Calculate the empirical formula for each of the following stimulants based on their elemental mass percent composition.nicotine (found in tobacco leaves): C 74.03%, H 8.70%, N 17.27%
Calculate the empirical formula for each of the following stimulants based on their elemental mass percent composition.caffeine (found in coffee beans): C 49.48%, H 5.19%, N 28.85%, O 16.48%
The elemental mass percent composition of ascorbic acid (vitamin C) is 40.92% C, 4.58% H, and 54.50% O.Determine the empirical formula of ascorbic acid.
The koala dines exclusively on eucalyptus leaves. Its digestive system detoxifies the eucalyptus oil, a poison to other animals. The chief constituent in eucalyptus oil is a substance called eucalyptol, which contains 77.87% C, 11.76% H, and the remainder O.What is the empirical formula for this substance?
An oxybromate compound, KBrOx, where x is unknown, is analyzed and found to contain 47.85 % Br. You may want to reference (Pages 99 - 102) Section 3.5 while completing this problem.What is the value of x?
The elemental mass percent composition of ibuprofen (a nonsteroidal anti-inflammatory drug [NSAID]) is 75.69 % C, 8.80 % H, and 15.51 % O.Determine the empirical formula of ibuprofen.
A chromium-containing compound has the formula FexCryO4 and is 28.59% oxygen by mass.Find x.
A chromium-containing compound has the formula FexCryO4 and is 28.59% oxygen by mass.Find y.
The elements X and Y form a compound that is 40% X and 60% Y by mass. The atomic mass of X is twice that of Y.What is the empirical formula of the compound?
A compound is 52.14% C, 13.13% H, and 34.73% O by mass. You may want to reference (Page 114) Section 3.10 while completing this problem.What is the empirical formula of the compound?
You may want to reference (Pages 116 - 119) Section 3.10 while completing this problem.Ibuprofen has the following mass percent composition: C 75.69%, H 8.80%, O 15.51%. What is the empirical formula of ibuprofen?
Vanadium forms four different oxides in which the percent by mass of vanadium is respectively 76 % , 68 % , 61 % , and 56 % .Give the name of the first oxide.
Vanadium forms four different oxides in which the percent by mass of vanadium is respectively 76 % , 68 % , 61 % , and 56 % .Give the name of the second oxide.
Vanadium forms four different oxides in which the percent by mass of vanadium is respectively 76 % , 68 % , 61 % , and 56 % .Give the name of the third oxide.
Vanadium forms four different oxides in which the percent by mass of vanadium is respectively 76 % , 68 % , 61 % , and 56 % .Give the name of the fourth oxide.
Vanadium forms four different oxides in which the percent by mass of vanadium is respectively 76 % , 68 % , 61 % , and 56 % .Find the formula of the first oxide.
Vanadium forms four different oxides in which the percent by mass of vanadium is respectively 76 % , 68 % , 61 % , and 56 % .Find the formula of the second oxide.
Vanadium forms four different oxides in which the percent by mass of vanadium is respectively 76 % , 68 % , 61 % , and 56 % .Find the formula of the third oxide.
Vanadium forms four different oxides in which the percent by mass of vanadium is respectively 76 % , 68 % , 61 % , and 56 % .Find the formula of the fourth oxide.
Give the empirical formula of the following compound if a sample contains 40.0% C, 6.7% H, and 53.3% O by mass.
You may want to reference (Pages 99 - 102) Section 3.5 while completing this problem.Determine the empirical formula of the following compound if a sample contains 87.5% N and 12.5% H by mass.
Determine the empirical formulas of the compounds with the following compositions by mass.10.4% C, 27.8% S, and 61.7% Cl
Determine the empirical formulas of the compounds with the following compositions by mass.21.7% C, 9.6% O, and 68.7% F
Determine the empirical formulas of the compounds with the following compositions by mass.32.79% Na, 13.02% Al, and the remainder % F
You may want to reference (Pages 99 - 102) Section 3.5 while completing this problem. Determine the empirical formulas of the compounds with the following compositions by mass.55.3% K, 14.6% P, and 30.1% O
You may want to reference (Pages 99 - 102) Section 3.5 while completing this problem. Determine the empirical formulas of the compounds with the following compositions by mass.24.5% Na, 14.9% Si, and 60.6% F
You may want to reference (Pages 99 - 102) Section 3.5 while completing this problem. Determine the empirical formulas of the compounds with the following compositions by mass.62.1% C, 5.21% H, 12.1% N, and the remainder O
A compound isolated from the rind of lemons is found to be 88.14 % carbon and 11.86 % hydrogen by mass.What is the empirical formula?
You may want to reference (Pages 114 - 118) section 3.10 while completing this problem. Calculate the empirical formula for each of the following natural flavors based on their elemental mass percent composition.Methyl butyrate (component of apple taste and smell): 58.80%C, 9.87%H, and 31.33%O.
You may want to reference (Pages 114 - 118) section 3.10 while completing this problem. Calculate the empirical formula for each of the following natural flavors based on their elemental mass percent composition.Vanillin (responsible for the taste and smell of vanilla): 63.15%C, 5.30%H, and 31.55%O.
Element X forms three different compounds with element Y. Based on the information in this table what are the formulas of compounds 2 and 3?Compound              Formula              Mass of Y per gram of X     1                            XY   6                           2.82 g     2                            XY   ?                          1.41 g     3                            XY  ?                           0.94 g
Which of the following pairs of compounds have the same empirical formula?a. acetylene, C2H2, and benzene, C6H6
Gahnite is a naturally occurring mineral containing aluminum (Al), oxygen (O), and zinc (Zn). A sample of the pure mineral was analyzed, and the following results obtained (percentages are by mass): % Al = 29.54 %                  % O = 34.75 %                   % Zn = 35.71 % Based on this information find the empirical formula for gahnite.
Which of the following pairs of compounds have the same empirical formula?b. ethane, C2H6, and butane, C4H10
Which of the following pairs of compounds have the same empirical formula?c. nitrogen dioxide, NO2, and dinitrogen tetroxide, N2O4
Which of the following pairs of compounds have the same empirical formula?d. diphenyl ether, C12H10O, and phenol, C6H5OH
A compound containing only carbon, hydrogen, and nitrogen is analyzed and found to contain 54.48% carbon and 13.74% hydrogen. What is the correct empirical formula for the compound? A) C4H12N2 B) C2H8N C) C2H7N2 D) C2H6N E) C3H12N2
A compound is 54.53% C, 9.15% H, and 36.32% O by mass. What is its empirical formula? The molecular mass of the compound is 132 amu. What is the molecular formula?
A compound of P and O is 56.34% P by weight. What is the simplest formula of this compound?a. PO2b. P2O7c. P4O5d. P2O3e. P3O2
What is the empirical formula for Hg2(NO3)2? A) HgNO3 B) Hg(NO3)2 C) Hg2NO3 D) Hg4(NO3)4 E) Hg2(NO3)2
One molecule of a compound weighs 2.03 x l0 - 22 g. The compound is:a) SOb)SiO4 c)Al2O3 d)PdOe) none of these   
a. A compound is 53.31% C, 11.18% H,  and 35.51% O by mass. What is its empirical formula?b. The molecular mass of the compound is 90 amu. What is the molecular formula?
Write the empirical formula corresponding to the following molecular formula: (a) Al2Br6
Write the empirical formula corresponding to the following molecular formula: (b) C8H10
Fructose is a common sugar found in fruit. Elemental analysis of fructose gives the following mass percent composition: C 40.00%, H 6.72%, O 53.28%. The molar mass of fructose is 180. 16 g/mol. Find the molecular formula of fructose. 
Write the empirical formula corresponding to the following molecular formula: (c) C4H8O2
Write the empirical formula corresponding to the following molecular formula: (d) P4O10
Estrone, which contains only carbon, hydrogen, and oxygen, is a female sexual hormone that occurs in the urine of pregnant women. Combustion analysis of a 1.893 g sample of estrone produces 5.545 g of CO2 and 1.388 g H2O. The molar mass of estrone is 270.36 g/mol. Find the molecular formula for estrone. 
Write the empirical formula corresponding to the following molecular formula: (e) C6H4Cl2
Write the empirical formula corresponding to the following molecular formula: (f) B3N3H6.
Determine the molecular and empirical formula of the following: (a) the organic solvent benzene, which has six carbon atoms and six hydrogen atoms
Determine the molecular and empirical formula of the following: (b) the compound silicon tetrachloride, which has a silicon atom and four chlorine atoms and is used in the manufacture of computer chips
Determine the molecular and empirical formula of the following: (c) the reactive substance diborane, which has two boron atoms and six hydrogen atoms
Determine the molecular and empirical formula of the following: (d) the sugar called glucose, which has six carbon atoms, twelve hydrogen atoms, and six oxygen atoms
A 45.2 mg sample of phosphorus reacts with selenium to form 131.6 mg of the selenide. Determine the empirical formula of phosphorus selenide.
The molecular formula for the condensed structural formula of the hydrocarbon below is: a. C6H10 b. C8H15 c. C8H30 d. C5H30 e. C8H16
A chemist decomposes samples of several compounds; the masses of their constituent elements are shown below. Calculate the empirical formula for each compound. a. 1.245 g Ni, 5.381 g I
A chemist decomposes samples of several compounds; the masses of their constituent elements are shown below. Calculate the empirical formula for each compound. b. 2.677 g Ba, 3.115 g Br
A chemist decomposes samples of several compounds; the masses of their constituent elements are shown below. Calculate the empirical formula for each compound. c. 2.128 g Be, 7.557 g S, 15.107 g O
The molecular formula for the condensed structural formula of the hydrocarbon below is: a. C5H10 b. C10H15 c. C15H30 d. C5H30 e. C15H10
Which of the following is NOT an empirical formula?a. CHOb. CH2Oc. C2H4Od. C2H4O2
Choose the incorrect statement. a. The molecular formula represents an actual molecule of the element or compound. b. The unit formula represents the smallest electrically neutral collection of ions of a compound. c. The empirical formula for any type of compound represents the relative number of atoms of each element in the compound. d. The stereochemical formula gives the same information as the structural formula, and in addition gives the arrangement of bonded and non-bonded valence electrons around each atom in the molecule. e. The structural formula gives the same information as the molecular formula, and in addition gives the connectivity of atoms.  
Calculate the empirical formula for each natural flavor based on its elemental mass percent composition: a. methyl butyrate ( component of apple taste and smell): C 58.80%, H 9.87%, O 31.33%
Calculate the empirical formula for each natural flavor based on its elemental mass percent composition: b. vanillin (responsible for the taste and smell of vanilla): C 63.15%, H 5.30%, O 31.55%
Which of the following statements is  false concerning the formula of a compound? a) The molecular formula and empirical formula can be identical. b) The molecular formula is the true ratio of atoms in a compound. c) The number of atoms in a molecular formula is always greater than the number of atoms in an empirical formula. d) The empirical formula is the simplest whole numbered ratio of atoms in a compound.
Researchers obtained the following data from experiments to find the molecular formula of benzocaine, a local anesthetic, which contains only carbon, hydrogen, nitrogen, and oxygen. Complete combustion of a 3.54 g sample of benzocaine with excess O2 formed 8.49 g of CO2 and 2.14 g H2O. Another sample of mass 2.35 g was found to contain 0.199 g of N. The molar mass of benzocaine was found to be 165 g/mol. Find the molar formula benzocaine .
What is the empirical formula for a compound that contains 29% Na, 41% S, and 30% O by mass?a. Na2S2O3b. NaSO2 c. NaSO3d. Na2S2O6
Carminic acid, a naturally occurring red pigment extracted from the cochineal insect, contains only carbon, hydrogen, and oxygen. It was commonly used as a dye in the first half of the nineteenth century. It is 53.66% C and 4.09% H by mass. A titration required 18.02 mL of 0.0406 M NaOH to neutralize 0.3602 g carminic acid. Assuming that there is only one acidic hydrogen per molecule, what is the molecular formula of carminic acid?
A 45.2-mg sample of phosphorus reacts with selenium to form 131.6 mg of the selenide. Determine the empirical formula of phosphorus selenide. 
The molar mass and empirical formula of several compounds are listed below. Find the molecular formula of each compound. a. C4H9, 114.22 g/mol
The molar mass and empirical formula of several compounds are listed below. Find the molecular formula of each compound. b. CCI, 284.77 g/mol 
The molar mass and empirical formula of several compounds are listed below. Find the molecular formula of each compound. c. C3H2N, 312.29 g/mol 
Give the empirical formula for each of the compounds represented below.
Give the empirical formula for each of the compounds represented below.
Give the empirical formula for each of the compounds represented below.
Give the empirical formula for each of the compounds represented below.
Determine the molecular formulas to which the following empirical formulas and molar masses pertain.a. SNH (188.35 g/mol)
Determine the molecular formulas to which the following empirical formulas and molar masses pertain.b. NPCl 2 (347.64 g/mol)
Determine the molecular formulas to which the following empirical formulas and molar masses pertain.c. CoC4O4 (341.94 g/mol)
Determine the molecular formulas to which the following empirical formulas and molar masses pertain.d. SN (184.32 g/mol)
The most common form of nylon (nylon-6) is 63.68% carbon, 12.38% nitrogen, 9.80% hydrogen, and 14.14% oxygen. Calculate the empirical formula for nylon-6.
What is the molecular formula for a compound with an empirical formula of CH 2O if its experimentally determined molecular weight is 180 amu?a. CHOb. C12H22O1c. C6H12O6d. C3H4O3
The elements X and Y form a compound that is 40% X and 60% Y by mass. The atomic mass of X is twice that of Y. What is the empirical formula of the compound? 
A sample of urea contains 1.121 g N, 0.161 g H, 0.480 g C, and 0.640 g O. What is the empirical formula of urea?
Determine the molecular formula of a compound that has a molar mass of 92.0 g/mol and an empirical formula of NO2.A) N2O3B) N3O6C) N2O4D) NO2E) N2O5
Determine the molecular formula of a compound that contains 26.7% P, 12.1% N, and 61.2% Cl, and has a molar mass of 580 g/mol.
Maleic acid is an organic compound composed of 41.39% C, 3.47% H, and the rest oxygen. If 0.129 mol of maleic acid has a mass of 15.0 g, what are the empirical and molecular formulas of maleic acid?
A 3.927 sample of glycerin was found to contain 1.536 g carbon, 0.345 g hydrogen, and the rest oxygen. Find the empirical formula of glycerin.
Aspirin has the following mass percent composition: C 60.00%, H 4.48%, and O 35.52%. Its empirical formula is:
The empirical formula of a chemical compound is C3H8O3. Its approximate molar mass of 94 g/mol was found by experiment. Calculate its exact molar mass.
A pure sample of a new chemical compound was analyzed and was found to have the following mass percentages: Al 31.5%; O 56.1%; S 12.4%. What is the empirical formula of this compound? A) Al5O28S7 B) Al3O9S C) AlO2S2 D) Al4O14S7 E) AlO6S1.5
Methamphetamine is a drug that results in neurotoxicity, increased risk of Parkinson's disease, oral decay and shrinking of brain matter. A sample of methamphetamine is found to contain 80.48% carbon, 10.13% hydrogen, and 9.39% nitrogen. What is the empirical formula of methamphetamine?a. C10H15Nb. C20H30N2c. C8HNd. C9H27N
What is the empirical formula for the compound P4O6?
The empirical formula of styrene is CH; the molar mass of styrene is 104.14 g/mol. What number of H atoms are present in a 2.00-g sample of styrene?
Ascorbic acid has a molar mass of 176.14 g/mol . What is the molecular formula of ascorbic acid?
What is the empirical formula and empirical formula mass of the following compound?Ba3(PO4)2
What is the empirical formula and empirical formula mass of the following compound?Te4I16
Determine the empirical formulas for the following compounds:(a) caffeine, C8H10N4O2
Determine the empirical formulas for the following compounds:(b) fructose, C12H22O11
What is the empirical formula and empirical formula mass of the following compound?C4H8
Determine the empirical formulas for the following compounds:(c) hydrogen peroxide, H2O2
What is the empirical formula and empirical formula mass of the following compound?C3H6O3
Determine the empirical formulas for the following compounds:(d) glucose, C6H12O6
What is the empirical formula and empirical formula mass of the following compound?P4O10
What is the empirical formula and empirical formula mass of the following compound?Ga2(SO4)3
What is the empirical formula and empirical formula mass of the following compound?Al2Br6
Determine the empirical formulas for the following compounds:(e) ascorbic acid (vitamin C), C6H8O6
Determine the empirical formulas for the following compounds:(d) glucose, C6H12O6
Determine the empirical formulas for the following compounds:(a) acetic acid, C2H4O2
Determine the empirical formulas for the following compounds:(b) citric acid, C6H8O7
Determine the empirical formulas for the following compounds:(c) hydrazine, N2H4
Determine the empirical formulas for the following compounds:(d) nicotine, C10H14N2
Determine the empirical formulas for the following compounds:(e) butane, C4H10
Write the empirical formulas for the following compounds:
Write the empirical formulas for the following compounds:
Write the molecular and empirical formulas of the following compounds:
Write the molecular and empirical formulas of the following compounds:
Write the molecular and empirical formulas of the following compounds:
Write the molecular and empirical formulas of the following compounds:
Write the molecular and empirical formulas of the following compounds:
Write the molecular and empirical formulas of the following compounds:
Write the molecular and empirical formulas of the following compounds:
Calculate the empirical or molecular formula mass and the molar mass of each of the following minerals: (a) limestone, CaCO3 
Calculate the empirical or molecular formula mass and the molar mass of each of the following minerals:(b) halite, NaCl
Calculate the empirical or molecular formula mass and the molar mass of each of the following minerals:(c) beryl, Be3Al2Si6O18 
Calculate the empirical or molecular formula mass and the molar mass of each of the following minerals:(d) malachite, Cu2(OH)2CO3 
Calculate the empirical or molecular formula mass and the molar mass of each of the following minerals:(e) turquoise, CuAl6(PO4)4(OH)8(H2O)4
Write the molecular and empirical formulas of the following compounds:
What is the empirical formula and empirical formula mass of the following compound?C2H4
What is the empirical formula and empirical formula mass of the following compound?C2H6O2
What is the empirical formula and empirical formula mass of the following compound?N2O5
A compound of carbon and hydrogen contains 92.3% C and has a molar mass of 78.1 g/mol. What is its molecular formula?
Dichloroethane, a compound that is often used for dry cleaning, contains carbon, hydrogen, and chlorine. It has a molar mass of 99 g/mol. Analysis of a sample shows that it contains 24.3% carbon and 4.1% hydrogen. What is its molecular formula?
Determine the empirical and molecular formula for chrysotile asbestos. Chrysotile has the following percent composition: 28.03% Mg, 21.60% Si, 1.16% H, and 49.21% O. The molar mass for chrysotile is 520.8 g/mol.
A major textile dye manufacturer developed a new yellow dye. The dye has a percent composition of 75.95% C, 17.72% N, and 6.33% H by mass with a molar mass of about 240 g/mol. Determine the molecular formula of the dye.
Diazomethane is a highly poisonous, explosive compound. The reason it is explosive is that it readily evolves N2. Diazomethane has the following composition by mass: 28.57% C; 4.80% H; and 66.64% N. The molar mass of diazomethane is 42.04 g/mol. Find the molecular formula of diazomethane.
What is the molecular formula of the following compound?Empirical formula CH2 (ℳ = 42.08 g/mol)
What is the molecular formula of the following compound?Empirical formula NH2 (ℳ = 32.05 g/mol)
What is the molecular formula of the following compound?Empirical formula NO2 (ℳ = 92.02 g/mol)
What is the molecular formula of the following compound?Empirical formula CHN (ℳ = 135.14 g/mol)
The first sulfur-nitrogen compound was prepared in 1835 and has been used to synthesize many others. In the early 1980s, researchers made another such compound that conducts electricity like a metal. Mass spectrometry of the compound shows a molar mass of 184.27 g/mol, and analysis shows it to contain 2.288 g of S for every 1.000 g of N. What is its molecular formula?
What is the molecular formula of the following compound?Empirical formula CH (ℳ = 78.11 g/mol)
What is the molecular formula of the following compound?Empirical formula C3H6O2 (ℳ = 74.08 g/mol)
What is the molecular formula of the following compound?Empirical formula HgCl (ℳ = 472.1 g/mol)
What is the molecular formula of the following compound?Empirical formula C7H4O2 (ℳ = 240.20 g/mol)
What information do we need to determine the molecular formula of a compound from the empirical formula?
Determine the molecular formulas to which the following empirical formula and molar mass pertain: SNH (188.35 g/mol).
Determine the molecular formulas to which the following empirical formula and molar mass pertain: NPCl2 (347.64 g/mol).
Determine the molecular formulas to which the following empirical formula and molar mass pertain: CoC4O4 (341.94 g/mol).
Determine the molecular formulas to which the following empirical formula and molar mass pertain: SN (184.32 g/mol).
Serotonin (ℳ = 176 g/mol) transmits nerve impulses between neurons. It contains 68.2% C, 6.86% H, 15.9% N, and 9.08% O by mass. What is its molecular formula?
The empirical formula of styrene is CH; the molar mass of styrene is 104.14 g/mol. What number of H atoms are present in a 2.00-g sample of styrene?
A sample of a hydrocarbon (a compound consisting of only carbon and hydrogen) contains 2.59 x 1023 atoms of hydrogen and is 17.3% hydrogen by mass. If the molar mass of the hydrocarbon is between 55 and 65 g/mol, what amount (moles) of compound is present, and what is the mass of the sample?
Menthol (ℳ = 156.3 g/mol), the strong-smelling substance in many cough drops, is a compound of carbon, hydrogen, and oxygen. When 0.1595 g of menthol was burned in a combustion apparatus, 0.449 g of CO2 and 0.184 g of H2O formed. What is menthol’s molecular formula?
The compound dimethyl phthalate, used in insect repellants, is composed of carbon, hydrogen, and oxygen and has a molar mass of 194.2 g/mol. A 0.2572-g sample of the compound was burned in a combustion apparatus and 0.583 g of CO2 and 0.119 g of H 2O were collected. What is the molecular formula of dimethyl phthalate?
Cortisol (ℳ = 362.47 g/mol) is a steroid hormone involved in protein synthesis. Medically, it has a major use in reducing inflammation from rheumatoid arthritis. Cortisol is 69.6% C, 8.34% H, and 22.1% O by mass. What is its molecular formula?
Formic acid is responsible for the sting of ant bites. By mass, formic acid is 26.10% C, 4.38% H, and 69.52% O. The molar mass of formic acid is 46.02 g/mol. Determine the molecular formula of formic acid.
A hydrate of copper (II) chloride has the following formula: CuCl2 • xH2 O. The water in a 3.41-g sample of the hydrate was driven off by heating. The remaining sample had a mass of 2.69 g .Find the number of waters of hydration (x) in the hydrate.
A compound of X and Y is 1/3 {extstyle{1 over 3}}X by mass. The atomic mass of element X is 1/3 {extstyle{3 over 4}}the atomic mass of element Y.Find the empirical formula of the compound.
Epsom salts is a hydrated ionic compound with the following formula: MgSO4 • xH2 O. A 4.93 g sample of Epsom salts is heated to drive off the water of hydration. The mass of the sample after complete dehydration was 2.41 g.Find the number of waters of hydration (x) in Epsom salts.
Find the empirical formula of the following compound.0.063 mol of chlorine atoms combined with 0.22 mol of oxygen atoms.
Find the empirical formula of the following compound.2.45 g of silicon combined with 12.4 g of chlorine.
A given sample of a xenon fluoride compound contains molecules of the type XeF n, where n is some whole number. Given that 9.03 x 10 20 molecules of XeFn weigh 0.368 g, determine the value for n in the formula.
Find the empirical formula of the following compound.0.039 mol of iron atoms combined with 0.052 mol of oxygen atoms.
A 0.652-g sample of a pure strontium halide reacts with excess sulfuric acid. The solid strontium sulfate formed is separated, dried, and found to weigh 0.755 g. What is the formula of the original halide?
Find the empirical formula of the following compound.0.903 g of phosphorus combined with 6.99 g of bromine.
A sample of urea contains 1.121 g N, 0.161 g H, 0.480 g C, and 0.640 g O. What is the empirical formula of urea?
A sample of 0.600 mol of a metal M reacts completely with excess fluorine to form 46.8 g of MF2.What element is represented by the symbol M?
A 0.370-mol sample of a metal oxide (M 2O3) weighs 55.4 g.What element is represented by the symbol M?
Fluorine is so reactive that it forms compound with several of the noble gases. (a) When 0.327 g of platinum is heated in fluorine, 0.519 g of a dark red, volatile solid forms. What is its empirical formula?
Nicotine is a poisonous, addictive compound found in tobacco. A sample of nicotine contains 6.16 mmol of C, 8.56 mmol of H, and 1.23 mmol of N [1 mmol (1 millimole) = 10−3 mol]. What is the empirical formula of nicotine?
Determine the empirical formulas for compounds with the following percent compositions:(a) 15.8% carbon and 84.2% sulfur
Determine the empirical formulas for compounds with the following percent compositions:(b) 40.0% carbon, 6.7% hydrogen, and 53.3% oxygen
Determine the empirical formulas for compounds with the following percent compositions: (a) 43.6% phosphorus and 56.4% oxygen
Determine the empirical formulas for compounds with the following percent compositions:(b) 28.7% K, 1.5% H, 22.8% P, and 47.0% O
Polymers are large molecules composed of simple units repeated many times. Thus, they often have relatively simple empirical formulas. Calculate the empirical formulas of the following polymers: (a) Lucite (Plexiglas); 59.9% C, 8.06% H, 32.0% O
Polymers are large molecules composed of simple units repeated many times. Thus, they often have relatively simple empirical formulas. Calculate the empirical formulas of the following polymers:(b) Saran; 24.8% C, 2.0% H, 73.1% Cl
Polymers are large molecules composed of simple units repeated many times. Thus, they often have relatively simple empirical formulas. Calculate the empirical formulas of the following polymers:(c) polyethylene; 86% C, 14% H
Polymers are large molecules composed of simple units repeated many times. Thus, they often have relatively simple empirical formulas. Calculate the empirical formulas of the following polymers:(d) polystyrene; 92.3% C, 7.7% H
Polymers are large molecules composed of simple units repeated many times. Thus, they often have relatively simple empirical formulas. Calculate the empirical formulas of the following polymers:(e) Orlon; 67.9% C, 5.70% H, 26.4% N
A compound with molar mass 180.1 g/mol has the following composition by mass:Determine the empirical and molecular formulas of the compound.
Find the empirical formula of the following compound.27.3 mass % carbon and 72.7 mass % oxygen
Narceine is a narcotic in opium that crystallizes from solution as a hydrate that contains 10.8 mass % water and has a molar mass of 499.52 g/mol. Determine x in narceine·xH2O.
Find the empirical formula of the following compound.a hydrocarbon with 79.9 mass % carbon
If an oxide of nitrogen contains 30.45 mass % N. What is the empirical formula of the oxide?
An oxide of nitrogen contains 30.45 mass % N. If the molar mass is 90 ± 5 g/mol, what is the molecular formula?
A chloride of silicon contains 79.1 mass % Cl. What is the empirical formula of the chloride?
A chloride of silicon contains 79.1 mass % Cl. If the molar mass is 269 g/mol, what is the molecular formula?
A compound that contains only carbon, hydrogen, and oxygen is 48.64% C and 8.16% H by mass. What is the empirical formula of this substance?
The most common form of nylon (nylon-6) is 63.68% carbon, 12.38% nitrogen, 9.80% hydrogen, and 14.14% oxygen. Calculate the empirical formula for nylon-6.
The compound adrenaline contains 56.79% C, 6.56% H, 28.37% O, and 8.28% N by mass. What is the empirical formula for adrenaline?
Adipic acid is an organic compound composed of 49.31% C, 43.79% O, and the rest hydrogen. If the molar mass of adipic acid is 146.1 g/mol, what are the empirical and molecular formulas for adipic acid?
Vitamin A has a molar mass of 286.4 g/mol and a general molecular formula of C xHyE, where E is an unknown element. If vitamin A is 83.86% C and 10.56% H by mass, what is the molecular formula of vitamin A?
For many years after they were discovered, it was believed that the noble gases could not form compounds. Now we know that belief to be incorrect. A mixture of xenon and fluorine gases, confined in a quartz bulb and placed on a windowsill, is found to slowly produce a white solid. Analysis of the compound indicates that it contains 77.55% Xe and 22.45% F by mass.(a) What is the formula of the compound?
What is empirical formula of a coumpound that contain 38.7% K, 13.9%N, 47.4% O by mass.
Limonene is a terpene found in the rind of lemon and other citrus fruits, contributing to their odor. The structure of limonene is shown at the right as a line structure (line-angle) drawing. Write the chemical formula for limonene. 
A sample of an unknown contains 30.4% nitrogen and 69.6% oxygen. What is the empirical formula for this compound?
A compound with the ompirical formula CH2 has a molar mass of 98 g/mol. What is the moleclar formuta for this compound?
A 51.94 gram sample of iron is heated in the presence of excess oxygen. A metal oxide is formed with a mass of 74.26 g. Determine the empirical formula of the metal oxide. Enter the elements in the order Fe, O
Which of the following compounds have the same empirical formula? Select all that apply. a. C6H16 b. C8H18 c. C12H24 d. C3H8 e. CH4 f. C2H6
What is the molecular formula of the following compound? empirical formula NH2Cl molar mass 103 g/mol. Express your answer as a chemical formula. 
A compound is 50.04% S and 49.95% O. What is the empirical formula? a. SO2 b. SOc. SO3 d. S2Oe. S2O3
A 15.19 gram sample of cobalt is heated in the presence of excess chlorine. A metal chloride is formed with a mass of 42.61 g. Determine the empirical formula of the metal chloride. Enter the elements in the order Co, Cl.
A molecule of a certain compound contains two nitrogen atoms and four oxygen atoms. What is the molecular formula for this compound? Use the Xy button to subscript the numbers.
Measurements show that unknown compound X has the following composition: elements               mass%carbon                    63.1%hydrogen                5.29%oxygen                   31.5%Write the empirical chemical formula of X.
What is the empirical formula of a compound composed of 35.9 g potassium (K) and 7.35 g oxyen (O)? 
It is often possible to change a hydrate into an anhydrous compound by heating it to drive off the water (dehydration). A 40.39 gram sample of a hydrate of Ca(NO3)2 was heated thoroughly in a porcelain crucible, until its weight remained constant. After heating, 28.07 grams of the anhydrous compound remained. What is the formula of the hydrate? Use a period instead of a dot in the formula of the hydrate.
Fill in the name and empirical formula of each ionic compound that could be formed from the ions in this table:
Determine the empirical formula of the following compound if a sample contains 87.5% N and 12.5% H by mass. Express your answer as a chemical formula.
What is the molecular formula for
What is the molecular formula for each of the following compounds? (a) Empirical formula: CH: Molar Mass of compound = 78.11 g/mol (b) Empirical formula: C3H6O2: Molar Mass of compound = 74.08 g/mol (c) Empirical formula: HgCl: Molar Mass of compound = 472.1 g/mol(d) Empirical formula: C7H4O2: Molar Mass of compound = 240.20 g/mol
To understand what an empirical formula is and to team the procedure for finding empirical formulas. An empirical formula expresses the simplest ratio of the elements involved. The compound P4O10 has a P.O ratio of 4:10. However this ratio can be simplified to 2:5. Therefore the empirical formula for P4O10 is P2O5. Another example is hydrogen peroxide, which has the formula H2O2 and an empirical formula of HO. One way that oho mists analyze new or unknown compounds it to determine the percentage composition of elements experimentally, which yields the empirical formula.Part AWhat is the empirical formula for the compound P4O6? Express your answer as a chemical formula. A compound is 80.0% carbon and 20.0% hydrogen by mass. Assume a 100 -g sample of this compound. Part BHow many grams of each element ore in this sample? Enter the number of grams of carbon followed by the number of grams of hydrogen, separated by a comma (e g , 30.0, 70.0). 
Click in the answer box to activate the palette. What is the molecular formula of the following compound?Empirical formula: C7H4O2 (M = 240.20 g/mol):
A 41.6 mg sample of carbon reacts with sulfur to form 116 mg of the compound. What is the empirical formula of the carbon sulfide? Express your answer as a chemical formula. 
A 49.29 gram sample of chromium is heated in the presence of excess oxygen. A metal oxide is formed with a mass of 72.03 g. Determine the empirical formula of the metal oxide. Enter the elements in the order Cr, O.
What is the molecular formula of each of the following compounds? Part Aempirical formula HCO2, molar mass = 90.0 g/mol. Express your answer as a chemical formula.Part Bempirical formula C2H4O, molar mass = 88 g/mol. Express your answer as a chemical formula.
Be sure to answer all parts.What are the empirical formula and empirical formula mass for C 3H6O3? 
An unknown compound has the following chemical formula: N2Ox where x stands for a whole number. Measurements also show that a certain sample of the unknown compound contains 3.7 mol of oxygen and 2.45 mol of nitrogen. Write the complete chemical formula for the unknown compound.
What is the molecular formula of the following compound? empirical formula CH2, molar mass 112.0 g/molExpress your answer as a chemical formula.
A compound is found to contain 22.56% phosphorus and 77.46% chlorine by mass. To answer the question, enter the elements in the order presented above.QUESTION 1The empirical formula for this compound is _____________ . QUESTION 2The molar mass for this compound is 137.3 g/mol. The molecular formula for this compound is _____________ . 
A sample of an iron-containing compound is 22.0% iron, 50.2% oxygen, and 27.8% chlorine by mass. What is the empirical formula of this compound?
The elemental mass percent composition of aspirin is 60.00% C, 4.48% H, and 35.52% O. Part ADetermine the empirical formula of aspirin. Express your answer as a chemical formula.
A 9.81 g sample of a compound contains 3.13 g potassium (K), 2.84 g chlorine (Cl), and oxygen (O). Calculate the empirical formula. 
A compound is found to contain 10.37% phosphorus, 4.689% nitrogen , and 84.95% iodine by mass. To answer the question, enter the elements in the order presented above. QUESTION 1:The empirical formula for this compound is ___________.QUESTION 2:The molecular weight for this compound is 298.8 amu. The molecular formula for this compound is ___________.
A compound is found to contain 64.80% carbon, 13.62% hydrogen, and 21.58% oxygen by mass. To answer the question, enter the elements in the order presented above. QUESTION 1:The empirical formula for this compound is __________.QUESTION 2:The molecular weight for this compound is 74.14 amu. The molecular formula for this compound is __________.
A compound found in crude oil consists of 93.71% C and 6.29% H by mass The molar mass of the compound is 128 g/mol. What is its molecular formula?
A compound has the empirical formula CH3O and a formula mass of 62.10 amu. What is the molecular formula of the compound? (a) C3H9O3 (b) C4H12O4 (c) C2H6O2 (d) CH3O
Some of the formulas below could be either molecular or empirical formulas: however, some could only be molecular formulas. Which of the following formulas must be molecular formulas? Select all that apply (a) C8H10O2 (b) C2H4O2(c) C3H4O3(d) C5H9(e) HO
Some of the formulas below could be either molecular or empirical formulas; however H2O2CH2OPOC3H4O3C2H4O2
Which of the following is an example of an empirical formula? (a) C2H2O2 (b) C9H12 (c) C6H6(d) C9H18Cl2(e) N2O4
A compound with the empirical formula CH2 has a molar mass of 98 g/mol. What is the molecular formula for this compound?