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 balancing of chemical equations is based on the Law of Conservation of Mass, which states that matter cannot be created nor destroyed. This means that the number of reactant atoms must be the same as the number of product atoms. 

We call these elements, which don't change after a chemical reaction, immutable groups

Intro: Why Must We Balance Chemical Equations? 

A chemical equation serves as a symbolic representation of a chemical reaction and so knowing the numbers of each compounds involved is essential.


For the following equation the numbers in blue are called your coefficients and represent the number of moles for each compound shown. 

Balanced-Chemical-ReactionBalanced Chemical Equation

This written chemical reaction tells us a story that states, “2 moles of hydrogen, H­, react with 1 mole of oxygen , O­2 , to produce 2 moles of water, H2O. ” 


The numbers in red are the subscripts and combined with the coefficients give us the number of each particular element. 

Traditional-Balance Traditional Balance 

Determining the number of each element will also be needed for later calculations dealing with reaction stoichiometry, limiting reagent and identifying reaction types.


Instructions for Balancing

Balancing a chemical reaction doesn’t really require algebra, an Algebraic Balance or even a calculator. All you need to do is follow these instructions and you’ll be balancing like a pro. 


STEP 1: Set up a list for the elements that are reactants and another list for the elements that are products. If your numerical values in both lists don’t match then you’ll have to balance the chemical equation. 

 

The following chemical reaction deals with the combustion of gaseous butane: 

Balancing-with-states-with-phasesBalancing Combustion of Butane Equation


STEP 2: Start at the top and going down both lists make sure to balance each element one by one. 

 

Balancing-Equations-by-inspectionBalancing Equations by Inspection

STEP 3: At this point notice there are 4 carbon atoms as reactants versus 1 carbon atom as a product. 


Balance the number of carbon atoms by placing a “4” in front of CO­2. The “4” is distributed so the number of carbon and oxygen atoms are both affected.  

Balancing-carbon-atomsBalancing carbon atoms

STEP 4: Continuing down the lists we next balance the number of hydrogen atoms. 


The reactant side has 10 hydrogen atoms, while the product side has only 2 hydrogen atoms. So placing a 5 in front of H­2O will give 10 hydrogen atoms (2 x 5). 


Balancing hydrogen atoms

In addition the 5 in front of H2O is distributed to oxygen. We now have 5 oxygen atoms from H2O and 8 oxygen atoms from CO2, giving us a current total of 13 oxygen atoms. 


STEP 5: At this point we need to balance our oxygen atoms and in order to have 13 oxygen atoms on both sides we place “6.5” in front of O2 

Balancing-oxygen-atomsBalancing oxygen atoms


STEP 6: Although the chemical equation is balanced because both lists have identical numerical values, you want your coefficients to be whole numbers and not decimals or fractions. 

 

Balancing-equations-with-decimals-and-fractionsBalancing equations with decimals and fractions


STEP 7: This additional step is only necessary when you have a decimal or fraction as a coefficient. When balancing a chemical equation you need all the coefficients to be whole numbers. 


In this example, in order to convert 6.5 into a whole number we multiply the entire chemical equation by 2. 


Balanced-Chemical-EquationBalanced Chemical Equation


FOR EXPERTS ONLY: Eventually if you keep up with your chemistry studies you’ll be asked to do more advanced chemical reactions (redox, acids and bases, precipitation) while using simple stoichiometry. 


You may have to balance redox reactions in acidic solutions or basic solutions. Again you won’t have to balance these reactions algebraically or with advanced math. 


You may even be given just the reactants without the products. In this case you’ll have to deal with charges that are written as superscripts. These charged ions will be in the form of a cation and an anion and will include finding the net ionic equation.




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
When the chemical equation for the complete combustion of toluic acid, CH3C6H4CO2H, to form carbon dioxide and water is balanced, the coefficient in front of the O 2 is a. 4 b. 10 c. 9 d. 5 e. 20
What are the coefficients for the decomposition of nitroglycerin? __ C3H5N3O9  → __ N2 + __ CO2 + __ H2O + __ O2 A. 2,3,6,2,1 B. 2,3,6,5,1 C. 4,6,12,10,12 D. 4,3,12,10,1 E. 4,6,12,10,1
Balance the following chemical equation. PCl3(l) + H2O(l) → H3PO3(aq) + HCl(aq)
What is the sum of the coefficients for the products in the following chemical equation? ______ C12H26 (g) + ______ O2 (g) → ______ CO2 (g) + ______ H2O (l)
What is the coefficient of aluminum phosphate once the reaction below is balanced?   ______ Hg3(PO4)2 (aq) + ______ Al (s) → ______ AlPO 4 (s) + ______ Hg (l)
When the equation below is balanced with the smallest set of coefficients, what is the coefficient of Zn? Zn + HNO3 → Zn(NO3)2 + NH4NO3 + H2O a. 1 (no coefficient written) b. 2 c. 3 d. 4 e. 6
When the following equation is balanced, the coefficient of sulfur dioxide is _____.  PbS (s) + O2 (g) → PbO (s) + SO2 (g)  A. 5  B. 1  C. 3  D. 2  E. 4
Write the balanced equation for the following reaction: aqueous sodium sulfide reacts with aqueous iron (III) nitrate to form aqueous sodium nitrate and solid iron (III) sulfide. What are the coefficients in the balanced reaction (write the substances in the order given)? A. 1, 1, 1, 3           B. 1, 2, 2, 3           C. 3, 2, 6, 1  D. 2, 3, 1, 6           E. 3, 1, 1, 3
What is the sum of the coefficients for the reactants in the balanced equation for the combustion of isopropyl alcohol: ______C3H8O + ______O2      →      ______CO2 + ______H2O a) 25 b) 13 c) 11 d) 6 e) none of the given answers
Balance the following chemical equations involving boron and/or fluorine: 1. B + Br2 → BBr3   2. B2O3 + C → B4C + CO   3. F2 + H2O → O2 + HF
After the following equation is balanced with the smallest possible whole numbers, what is the sum of the coefficients? NO2(g) + H2(g) → NH3(g) + H2O (l) (A) 4 (B) 10 (C) 15 (D) 17 (E) 20
Dinitrogen pentoxide is a gas that decomposes to form nitrogen dioxide gas and oxygen gas. Write a balanced equation for the reaction, and be sure to include the states of matter.
Balance this equation using the smallest possible integers, S + HNO3 → H2SO4 + NO2 + H2O. What is the coefficient of the water? (A) 1 (B) 2 (C) 4 (D) 6 (E) 10
Balance this equation using the smallest possible integers, NO + NH3 → N2 + H2O. What is the coefficient of the water? (A) 1 (B) 2 (C) 3 (D) 6 (E) 12
Balance the following chemical equations:
What is the coefficient of oxygen in the balanced combustion reaction of one (1) mole of acetone (C3H6O)? a. 1 b. 2 c. 3 d. 4 e. 5
What is the sum of the coefficients when the following equation is balanced with the smallest whole number coefficients? C12H10O + O2 → CO2 + H2O (A) 31 (B) 32 (C) 64 (D) 65 (E) None of the above  
When the following equation is balanced, the coefficient of sulfur dioxide is _______.  PbS (s) + O2 (g) → PbO (s) + SO2 (g) a. 5 b. 1 c. 3 d. 2 e. 4  
A reaction occurs between calcium nitrate and ammonium fluoride, producing calcium fluoride, dinitrogen monoxide, and water vapor. The correct set of stoichiometric coefficients, respectively, for the balanced reaction is: A) 3 6 6 3 4 B) 3 2 1 2 2 C) 1 2 2 1 1 D) 1 2 1 2 4 E) 2 1 2 2 2
Write the chemical equation for the following reaction:Sulfur dioxide gas reacts with oxygen gas to form sulfur trioxide gas.
Aqueous nitric acid and aqueous ammonia react.Express your answer as a balanced chemical equation. Identify all of the phases in your answer.
Balance each chemical equation:a. Na2S(aq) + Cu(NO3)2(aq) → NaNO3(aq) + CuS(s)
Write the balanced chemical equation for the following reaction. Phases are optional.Solid iron(III) oxide reacts with hydrogen gas to form solid iron and liquid water.
Balance  the following equations by inserting coefficients as needed.— Li3N  +  — H2O →  — LiOH  +  — NH 3— ZnO  + — CO → — Zn  + — CO2— SO2  +  — O2 →  — SO3
Write the balanced chemical equation for the reaction shown here. 
Write the balanced chemical equations.Nitric acid forms when gaseous nitrogen dioxide reacts with gaseous oxygen and liquid water.
For each of the following equations, write the chemical formulas and balance the equation. Try to indicate all the physical states (solid, liquid, gas) as well.a) potassium + water → potassium hydroxide + hydrogen  b) potassium hydride + water → potassium hydroxide + hydrogen  c) silicon dioxide + carbon → silicon carbide + carbon monoxide  d) silicon dioxide + hydrogen fluoride → silicon tetrafluoride + water  e) phosphorus + chlorine → phosphorous tetrachloride
Write the balanced chemical equation: Aqueous hydrochloric acid reacts with solid manganese(IV) oxide to form aqueous manganese(II) chloride, liquid water, and chlorine gas.
Balance the equation. HC2H3O2(aq) +    Ba(OH)2(aq) →    H2O(l) +    Ba(C2H3O2)2(aq)
Balance each chemical equation:b. N2H4(l) → NH3(g) + N2(g)
Complete and balance the following chemical equation. Name the product.Ba + H2O →  
What is the coefficient of O 2 when the following equation is properly balanced with the smallest set of whole numbers?   C3H7OH(I) + O2(g) → CO2 + H2O A) 5 B) 17 C) 9 D) 6 E) 2
Balance each chemical equation:c. HCl(aq) + O2(g) → H2O(l) + Cl2(g)
Balance each chemical equation:d. FeS(s) + HCl(aq) → FeCl2(aq) + H2S(g)
What is the stoichiometric coefficient for oxygen gas (O2) when the following equation is balanced using the lowest, whole-number coefficients? _____C3H8(g) + _____ O2(g)  →  _____ CO2(g) + _____ H2O(l)   A) 9               B) 7             C) 5                 D) 3                 E) 1
Balance this equation:KOH+H3PO4 → K3PO4+H2O 
When iron rusts, solid iron reacts with gaseous oxygen to form solid iron (III) oxide. Write a balanced chemical equation for the reaction.  Express as a chemical equation, identify all the phases in the answer.
Write a balanced equation to show the reaction of aqueous aluminum acetate with aqueous ammonium phosphate to form solid aluminum phosphate and aqueous ammonium acetate.A) Al(C2H3O2)2(aq) + (NH4)2PO4(aq) → AlPO4(s) + 2 NH4C2H3O2(aq)B) Al(C2H3O2)2(aq) + (NH3)2PO4(aq) → AlPO4(s) + 2 NH3C2H3O2(aq)C) Al(CO3)2(aq) + (NH3)2PO4(aq) → AlPO4(s) + 2 NH3CO3(aq)D) Al(C2H3O2)3(aq) + (NH4)3PO4(aq) → AlPO4(s) + 3 NH4C2H3O2(aq)E) Al(CO2)3(aq) + (NH4)3PO3(aq) → AlPO3(s) + 3 NH4CO2(aq)
Balance the following equations by inserting coefficients as needed.a.  — C3H8 + — O2 → — CO2 + — H2Ob.  — P4O10 +  — H2O →  — H3PO4  
Determine the balanced chemical equation for this reaction.C8H18(g) + O2(g) → CO2(g) + H2O(g)
How do you balance this equation? NaOH + H2O → Na + OH 
Balance the following equation: B2O3(s) + HF(l) → BF3(g) + H2O(l) A)  B2O3 (s) + 6HF(l) → 2BF3 (g) + 3H2O(l) B)  B2O3 (s) + H6F6(l) → B2F6(g) + H6O3 (l) C)  B2O3 (s) + 2HF(l) → 2BF3 (g) + H2O(l) D)  B2O3 (s) + 3HF(l) → 2BF3 (g) + 3H2O(l) E)  B2O3 (s) + 6HF(l) → 2BF3 (g) + 6H2O(l)
What is the coefficient of H2O when the following equation is properly balanced with the smallest set of whole numbers?  ___ Na + ___ H2O → ___ NaOH + ___ H2 A)  1                       B)  2                       C)  3                       D)  4                      E)  5
What is the coefficient of H2O when the following equation is properly balanced with the smallest set of whole numbers?                                           ___ Al4C3 + ___ H2O → ___ Al(OH)3 + ___ CH4 A)  3                       B)  4                       C)  6                       D)  12                    E)  24
Write the chemical formulas for the following reaction. Do not worry about balancing or states:Sulfurous acid reacts with barium hydroxide to form water and barium sulfite.
Complete and balance each of the following equations for combustion reactions.a. C(s)+O2(g)→Express your answer as a chemical equation. Identify all of the phases in your answer.b. CS2(s)+O2(g) →Express your answer as a chemical equation. Identify all of the phases in your answer.c. CH4O(l)+O2(g) →Express your answer as a chemical equation. Identify all of the phases in your answer. 
When the chemical equation below is balanced with the smallest INTEGER coefficients, the sum of the coefficients is: (H3C)2PCH2N(CH3)2 + O2 → CO2 + H3PO4 + N2 + H2O a. 13 b. 91 c. 35 d. 41 e. 33
Complete the following reaction. Express your answer as a chemical equation. Identify all of the phases in your answer.C4H10S(l) + O2(g) →
When the chemical equation FeS + O2 → FeO + SO2 is balanced with the smallest integral coefficients, the coefficient of O 2 is: a. 3 b. 2 c. 4 d. 8 e. 5
The reaction of calcium with elemental chlorine yields calcium chloride. Write a balanced chemical equation for this reaction.a) Ca(s) + Cl2(g) → CaCl(s) + Cl(g)b) Ca(s) + Cl2(g) → CaCl2(s)c) Ca(s) + 2 Cl2(g) → CaCl4(s)d) 2 Ca(s) + Cl2(g) → 2 CaCl(s)e) 4 Ca(s) + Cl2(g) → 2 Ca2Cl(s)
Examine the following unbalanced chemical equation: CO2 + C → COWhich of the following is the correctly balanced form of this equation? a. CO2 + C → C2O b. CO2 + C → 2CO c. 2CO2 + C → CO d. CO2 + C2 → CO
Which one of the following chemical equations is balanced? a. 2Na + S → 2NaS b. NH3 + H2O → 2NH4OH c. KOH + H2SO4 → KHSO4 + H2O d. 2NaCl + H2SO4 → HCl + NaSO4
Balance the following equations by inserting coefficients as needed.a. CaCO3 + HCl → CaCl2 + CO2 + H2Ob. C6H12O2 + O2 → CO2 + H2O
Determine the balanced chemical equation for this reaction. C8H18(g) + O2(g) → CO2(g) + H2O(g)
Write a balanced equation to show the reaction of gaseous ethane with gaseous oxygen to form carbon monoxide gas and water vapor.A) 2 C2H6 (g) + 7 O2 (g) → 4 CO2 (g) + 6 H2O (g)B) C2H6 (g) + 5 O (g) → 2 CO (g) + 3 H2O (g)C) 2 C2H6 (g) + 5 O2 (g) → 4 CO (g) + 6 H2O (g)D) C2H6 (g) + 7 O (g) → 2 CO2 (g) + 3 H2O (g)E) 2 CH3 (g) + 5 O (g) → 2 CO (g) + 3 H2O (g)
Write a balanced equation to show the reaction of aqueous aluminum acetate with aqueous ammonium phosphate to form solid aluminum phosphate and aqueous ammonium acetate.A) Al(C2H3O2)2 (aq) + (NH4)2PO4 (aq) → AlPO4 (s) + 2 NH4C2H3O3 (aq)B) Al(C2H3O2)2 (aq) + (NH3)2PO4 (aq) → AlPO4 (s) + 2 NH3C2H3O3 (aq)C) Al(CO3)2 (aq) + (NH3)2PO4 (aq) → AlPO4 (s) + 2 NH3CO3 (aq)D) Al(C2H3O2)3 (aq) + (NH4)3PO4 (aq) → AlPO4 (s) + 3 NH4C2H3O3 (aq)E) Al(CO2)3 (aq) + (NH4)3PO3 (aq) → AlPO3 (s) + 3 NH4CO2 (aq)
A 54 g sample of aluminum reacts completely with 48.0 g of oxygen gas. Which is the formula of the oxide?a. Al2O3 b. AlOc. AlO2d. Al6O5e. Al3O5
Write the balanced chemical formula for the reaction in which the reactant potassium chlorate is broken down into two products: potassium chloride and oxygen.
Nitric oxide gas reacts with hydrogen gas to form ammonia gas and water vapor. What is the balanced equation?
Liquid octane reacts with oxygen gas to form carbon dioxide gas and water vapor. What is the balanced chemical equation?
Give the balanced equation for each of the following.a. The combustion of ethanol (C2H5OH) forms carbon dioxide and water vapor. A combustion reaction refers to a reaction of a substance with oxygen gas.
Give the balanced equation for each of the following.b. Aqueous solutions of lead(II) nitrate and sodium phosphate are mixed, resulting in the precipitate formation of lead(II) phosphate with aqueous sodium nitrate as the other product.
Give the balanced equation for each of the following.c. Solid zinc reacts with aqueous HCl to form aqueous zinc chloride and hydrogen gas.
Give the balanced equation for each of the following.d. Aqueous strontium hydroxide reacts with aqueous hydrobromic acid to produce water and aqueous strontium bromide. 
Balance the following equations:a. Ca(OH)2(aq) + H3PO4(aq) → H2O(l) + Ca3(PO4)2(s) 
Balance the following equations:b. Al(OH)3(s) + HCl(aq) → AlCl3(aq) + H2O(l) 
Balance the following equations:c. AgNO3(aq) + H2SO4(aq) → Ag2SO4(s) + HNO3(aq) 
Balance each of the following chemical equations.a. KO2(s) + H2O(l) → KOH(aq) + O2(g) + H2O2(aq) 
Balance the following equation: K2CrO4 + Na 2SO3 + HCl →  KCl + Na 2SO4 + CrCl3 + H2O Enter the coefficients for each compound seperated by commas, in the order in which they appear in the equation.
Balance each of the following chemical equations.b. Fe2O3(s) + HNO3(aq) → Fe(NO3)3(aq) + H2O(l) 
Balance each of the following chemical equations.c. NH3(g) + O2(g) → NO(g) + H2O(g) 
Balance each of the following chemical equations.d. PCl5(l) + H2O(l) → H3PO4(aq) + HCl(g) 
Balance each of the following chemical equations.e. CaO(s) + C(s) → CaC2(s) + CO2(g) 
Balance each of the following chemical equations.f. MoS2(s) + O2(g) → MoO3(s) + SO2(g)
Balance each of the following chemical equations.g. FeCO3(s) + H2CO3(aq) → Fe(HCO3)2(aq)
When the chemical reaction representing the complete combustion of acetic acid, C2H4O2, is balanced with the smallest integer coefficients, the sum of the coefficients in the balanced equation is: A. 9 B. 7 C. 2 D. 4 E. 5
Sulfuric acid is a component of acid rain formed when gaseous sulfur dioxide pollutant reacts with gaseous oxygen and liquid water to form aqueous sulfuric acid. Write a balanced chemical equation for this reaction. 
When iron rusts, solid iron reacts with gaseous oxygen to form solid iron(III) oxide. What is the balanced chemical equation?
Nitric acid is a component of acid rain that forms when gaseous nitrogen dioxide pollutant reacts with gaseous oxygen and liquid water to form aqueous nitric acid. Write a balanced chemical equation for this reaction. 
Write the described reaction as a balanced reaction equation: “Lead(II)nitrate solution is added to potassium iodide solution, which results in formation of solid lead(II)iodide while potassium nitrate remains in solution.”a) PbNO3(soln) + KI(soln) → PbI(solid) + KNO3(soln)b) Pb(NO3)2 + 2KI → 2PbI + 2KNO3c) Pb(NO3)2(aq) + KI2(s) → PbI2(s) + K(NO3)2(aq)d) Pb(NO2)(aq) + 2KI(aq) → PbK 2(s) + I2(NO2)(aq)e) Pb(NO3)2(aq) + 2KI(aq) → PbI 2(s) + 2KNO3(aq)
In a popular classroom demonstration, solid sodium is added to liquid water and reacts to produce hydrogen gas and aqueous sodium hydroxide. Write a balanced chemical equation for this reaction. 
One of relatively few reactions that takes place directly between two solids at room temperature isBa(OH)2 • 8H2O(s) + NH4SCN(s) → Ba(SCN)2(s) + H2O(l) + NH3(g)In this equation, the • 8H2O in Ba(OH) 2 • 8H2O indicates the presence of eight water molecules. This compound is called barium hydroxide octahydrate.a. Balance the equation.
One of relatively few reactions that takes place directly between two solids at room temperature isBa(OH)2 • 8H2O(s) + NH4SCN(s) → Ba(SCN)2(s) + H2O(l) + NH3(g)In this equation, the • 8H2O in Ba(OH) 2 • 8H2O indicates the presence of eight water molecules. This compound is called barium hydroxide octahydrate.b. What mass of ammonium thiocyanate (NH 4SCN) must be used if it is to react completely with 6.5 g barium hydroxide octahydrate?
When iron rusts, solid iron reacts with gaseous oxygen to form solid iron(III) oxide. Write a balanced chemical equation for this reaction. 
Write a balanced chemical equation for the fermentation of sucrose (C12H22O11) by yeasts in which the aqueous sugar reacts with water to form aqueous ethyl alcohol (C2H5OH) and carbon dioxide gas
After balancing the following reaction, what are the coefficients for H 2O and NaAu(CN)2, respectively? __ Au + __ NaCN + __ O2 + __ H2O → __ NaAu(CN)2 + __ NaOH A) 1, 3 B) 2, 4 C) 1, 4 D) 3, 2 E) 3, 1
Write a balanced equation for the photosynthesis reaction in which gaseous carbon dioxide and liquid water react in the presence of chlorophyll to produce aqueous glucose (C6H12O6) and oxygen gas.
Balance the following equation and select the correct coefficients for NO2 and N2, respectively: __ NH3 (g) + __ NO2 (g) → __ N2 (g) + __ H2O (l) a) 3, 5 b) 5, 9 c) 4, 3 d) 6, 7 e) 7, 9
Write a balanced chemical equation for each reaction: a. Solid copper reacts with solid sulfur to form solid copper (I) sulfide.
Write a balanced chemical equation for each reaction: b. Solid iron (III) oxide reacts with hydrogen gas to form solid iron and liquid water.
Write a balanced chemical equation for each reaction: c. Sulfur dioxide gas reacts with oxygen gas to form sulfur trioxide gas.
Write a balanced chemical equation for each reaction: d. Gaseous ammonia (NH3) reacts with gaseous oxygen to form gaseous nitrogen monoxide and gaseous water.
Write a  balanced equation to show the reaction of sulfurous acid with lithium hydroxide to form water and lithium sulfite.a. H2SO4 (aq) + LiOH (aq) → H2O (l) + Li 2SO4 (aq)b. H2SO3 (aq) + 2 LiOH (aq) → 2 H 2O (l) + Li2SO3 (aq)c. HSO3 (aq) + LiOH (aq) → H 2O (l) + LiSO3 (aq)d. HSO4 (aq) + LiOH (aq) → H 2O (l) + LiSO4 (aq)e. H2S (aq) + 2 LiOH (aq) → 2 H 2O (l) + Li 2S (aq) 
Write the balanced equation for the reaction of sodium hydroxide with sulfuric acid to give water and sodium sulfate.
When hydrogen peroxide (H2O2) decomposes, it forms oxygen and hydrogen gas:  ____ H2O2 → _____ O2 + _____ H2O When this equation is balanced, what is the coefficient for oxygen? a. 1 b. 2 c. 3 d. 4  
Write a balanced equation to show the reaction of aqueous aluminum acetate with aqueous ammonium phosphate to form solid aluminum phospate and aqueous ammonium acetate.A) Al(C2H3O2)2(aq) + (NH3)2PO4(aq) → AlPO4(s) + 2NH3C2H3O2(aq)B) Al(C2H3O2)2(aq) + (NH4)2PO4(aq) → AlPO4(s) + 2NH4C2H3O2(aq)C) Al(CO2)3(aq) + (NH4)3PO3(aq) → AlPO3(s) + 3NH4CO2(aq)D) Al(C2H3O2)3(aq) + (NH4)3PO4(aq) → AlPO4(s) + 3NH4C2H3O2(aq)E) Al(CO2)3(aq) + (NH3)2PO4(aq) → AlPO4(s) + 2NH3CO3(aq)
Write the chemical equation for the reaction:Solid iron(III) oxide reacts with carbon monoxide gas to form solid iron and carbon dioxide gas.
Balance the following equation:  K2CrO4 +   Na2SO3 +   HCl →   KCl +   Na 2SO4 +   CrCl3 +   H2O
Balance the following equations. a.  ___ C3H8O(l) + ____ O2(g) → ________ CO2(g) + ________ H2O(l) b. _____ PH3(g) + ____ O2(g) → _______ P4O10(s) + _______ H2O(g) c. ____ B2O3(s) + _____ HF(l) → _______ BF3(g) + _________ H2O(l) d) ____Cu2O(s) + ______O2(g) → ______CuO(s) e) ___CaCl2(aq) + ____K2CO3(aq) → ___ KCl(aq) + ____CaCO3(aq) f) ___ MgO(s) + ___ Fe(s) → ___ Fe2O3(s) + ___ Mg(s)  
Write a balanced chemical equation for each of the following.a. Aqueous hydrogen chloride reacts with oxygen gas to form chlorine gas and liquid water.b. Liquid octane reacts with oxygen gas to form carbon dioxide gas and water vapor.c. Nitric oxide gas reacts with hydrogen gas to form ammonia gas and water vapor.d. Solid iron(III) oxide reacts with carbon monoxide gas to form solid iron and carbon dioxide gas.
Balance the following equations.a. H2 + O2 → H2Ob. Mg + O2 → MgOc. SF4 + H2O → SO2 + HFd. P4 + O2 → P2O5e. C3H8 + O2 → CO2 + H2O
Write a balanced chemical equation for each of the following. Express your answer as a chemical equation. Identify all of the phases in your answer.a. Solid copper reacts with solid sulfur to form solid copper(I) sulfide.b. Liquid octane reacts with oxygen gas to form carbon dioxide gas and water vapor.c. Sulfur dioxide gas reacts with oxygen gas to form sulfur trioxide gas.d. Solid iron(III) oxide reacts with carbon monoxide gas to form solid iron and carbon dioxide gas.
Solid copper reacts with solid sulfur to form solid copper(I) sulfide. What is the balanced equation?
Balance the following equation: a. Zn +H2SO4 → ZnSO4 + H2 b. Al + H2SO4 → Al2(SO4)3 + H2
Write the balanced chemical equation for the following reaction. Phases are optional. The reaction of zinc metal and hydrochloric acid produces hydrogen and zinc chloride.
Write the balanced equation for the complete combustion of each of the following compounds.
Part AGaseous acetylene (C2H2) reacts with oxygen gas to form gaseous carbon dioxide and gaseous water. Express your answer as a chemical equation. Identify all of the phases in your answer. Part BChlorine gas reacts with aqueous potassium iodide to form solid iodine and aqueous potassium chloride. Express your answer as a chemical equation. Identity all of the phases in your answer. Cl2 (g) + 2KI (aq) → I2 (s) + 2KCl (aq) Part CSolid lithium oxide reacts with liquid water to form aqueous lithium hydroxide. Express your answer as a chemical equation. Identify all of the phases in your answer. Li2O (s) + H2O (l) → 2LiOH (aq)
In our bodies, sugar is broken down with oxygen to produce water and carbon dioxide. Write a balanced equation for the complete oxidation reaction that occurs when glucose (C6H12O6) reacts with oxygen. Use the smallest possible integer coefficients.
Phosphorus (P4) burns in air to give diphosphorus pentoxide. Write a balanced chemical equation for the reaction. 
Complete and balance the following reaction. Include states for all products. If no reaction occurs, write "No Reaction"H3PO4 (aq) + Al(OH)3(s) →
Consider this aqueous reaction. HCN (aq) + Be(OH)2 (aq) →What is the formula for the salt that forms?
Write and balance the equation for the complete combustion of heptane, C7H16. You do not need to include any phase symbols or energy changes.
Iron(III) oxide reacts with aluminum metal powder to make aluminum oxide and iron metal (and a whole lotta heat!). What are the stoichiometric coefficients for the balanced chemical equation (as written)? _____ Iron (III) oxide + ____ aluminum metal → _____ aluminum oxide + _____ iron metal
Automobile airbags inflate due to the formation of nitrogen gas from the following chemical reaction. 2NaN3 (s) → 3N2 (g) + 2Na (s) Identify the number of each atom in the reactants and products for this balanced reaction. 
Balance the following reactions: a. _____CaO (s) + _____C (s) → _____CaC 2 (s) + _____CO2 (g) b. _____P4O10 (s) + _____H2O (l) → _____H3PO4 (l)
A balanced reaction equation must have the same number of atoms of each element on both sides of the equation. The reaction given below represents the combustion of propanol. To verify that the equation is balanced, count the atoms of each element on both sties of the reaction. 2C3H7OH + 9O2 → 6CO2 + 8H2O Is the reaction balanced?              • yes               • no
Click in the box to activate the palette. Write a balanced equation for the following by inserting the correct coefficients. Al(NO3)3 (aq) + KOH(aq) → KNO 3 (aq) + Al(OH)3 (s)
Balance each of the following neutralization reactions. Part AHCl (aq) + Mg(OH)2 (s) → MgCl2 (aq) + H2O (l) Express your answer as a chemical equation. Identify all of the phases in your answer. Part BH3PO4 (aq) + NaOH(aq) → Na3PO4(aq) + H2O(l) Express your answer as a chemical equation. Identify all of the phases in your answer.
Click in the answer box to activate the palette. Convert the following into a balanced equation: Liquid disilicon hexachloride reacts with water to form solid silicon dioxide hydrogen chloride gas, and hydrogen gas. Be sure to include the state of each reactant and product in the equation.
The equilibrium system between sulfur dioxide gas, oxygen gas, and sulfur trioxide gas is given. 2SO2(g) + O2(g) ⇌ 2SO3(g) Write the balanced chemical equation for the reverse reaction. Include physical states for all species.
The Determine the balanced chemical equation for this reaction. C8H18 (g) + O2 (g) → CO2 (g) + H2O (g) Enter the coefficients for each compound in order, separated by commas. For example, 1,2,3,4 would indicate one mole of C8H18, two moles of O2, three moles of CO2, and four moles of H2O.
Balance each of the following neutralization reactions: Part A HNO3 (aq) + NaOH(s) → H2O(l) + NaNO3 (aq) Express your answer as a chemical equation. Identify all of the phases in your answer. Part B H2SO4 (aq) + KOH(s) → H2O(l) + K2SO4 (aq) Express your answer as a chemical equation. Identify all of the phases In your answer.
Check in the box to activate the palette.Write a balanced equation for the following by inserting the correct coeficients.Al(NO3)3 aq) + KOH(aq) → KNO3 (aq) + Al(OH)2 (s)
Click in the answer box to activate the palette.Convert the following into a balanced equation: When nitrogen dioxide is bubbled into water, a solution of nitric acid forms and gaseous nitrogen monoxide is released. Be sure to include the state of each reactant and product in the equation.
Complete the balanced equations for these reactions that were observed in the lab.___Zn (s) + ___ HCl (aq) → ZnCl2 (aq) + ___ H2 (g) ___ H2 (g) + ___ O2 + flame  →  ___ H2O (g) ___ H2O2 (l)  → ___ H2O (l) + ___ O2 (g) ___ O2 (g) + C + flame → ___ CO2 (g) (the carbon came from the glowing splint)
When methane (CH4) bums it reacts with oxygen gas to produce carbon dioxide and water. The unbalanced equation for this reaction is CH4 (g) + O2 (g) → CO2 (g) + H2O (g) This type of reaction is referred to as a complete combustion reaction. Part AWhat coefficients are needed to balance the equation for the complete combustion of methane? Enter the coefficients in the order CH4, O2, CO2, and H2O, respectively. Express your answer as four Integers, separated by commas (e g.. 1,2, 3, 4).
Polishing Silver Silver tamish is the result of silver metal reacting with sulfur compounds, such as H2S, in the air. The tamish on silverware (Ag2S) can be removed by soaking in a solution of NaHCO3 (baking soda) in a basin lined with aluminum foil. Write a balanced equation for the tarnishing of Ag to Ag2S. Do not include phases. How many moles of electrons are transferred per mole of silver? Write a balanced reaction for the reaction of Ag2S with Al metal and H2O to produce Al(OH)3, H2S, and Ag metal. Do not include phases.
When aluminum, Al, metal is dipped in an aqueous solution of hydrochloric acid, HCl, hydrogen gas H2 is produced with the formation of an aluminum chloride, AlCl2, solution. Write the balanced chemical equation showing the phase of reactants and products. Express your answer as a chemical equation including phases. 
When the following equation is balanced (without fractional coefficients), what is the coefficient of H2?Al + H2SO4 → Al2(SO4)3 + H2
Write and balance the equation for the complete combustion of heptane, C7H16. You do not need to include any phase symbols or energy changes. 
Determine which elements are balanced and which are unbalanced in the following partially balanced chemical equation. 2LiOH + H2SO4 → Li2SO4 + H2O 
Balance the following equations by inserting coefficients as needed. 1. NaH + H2O → NaOH + H22. SO2 + O2 → SO3