What is the minimum mass of ethylene glycol (C 2H6O2) that must be dissolved in 14.5 kg of water to prevent the solution from freezing at −12.0°F? (Assume ideal behavior.)
The boiling point of ethanol (C2H5OH) is 78.5°C. What is the boiling point of a solution of 6.4 g of vanillin (ℳ = 152.14 g/mol) in 50.0 g of ethanol (Kb of ethanol = 1.22°C/m)?
How many moles of solute particles are present in 1 mL of each of the following aqueous solutions?
(c) 0.08 M pyridine (C5H5N)
An automobile antifreeze mixture is made by mixing equal volumes of ethylene glycol (d = 1.114 g/mL; ℳ = 62.07 g/mol) and water (d = 1.00 g/mL) at 20°C. The density of the mixture is 1.070 g/mL. Express the concentration of ethylene glycol as:
Argon makes up 0.93% by volume of air. Calculate its solubility (mol/L) in water at 20°C and 1.0 atm. The Henry’s law constant for Ar under these conditions is 1.5×10–3 mol/L·atm.
Bismuth is used to calibrate instruments employed in high-pressure studies because it has several well-characterized crystalline phases. Its phase diagram (below) shows the liquid phase and five solid phases that are stable above 1 katm (1000 atm) and up to 300°C. Which phase is stable at 50 katm and 175°C?
Draw a Lewis structure for
Draw a Lewis structure for
Rank the members of the following set of compounds in order of decreasing ionic character of their bonds. Use partial charges to indicate the bond polarity of each:
(a) PCl3, PBr3, PF3
Arrange each set of atoms in order of decreasing IE1:
(a) Na, Li, K
During World War II, a portable source of hydrogen gas was needed for weather balloons, and solid metal hydrides were the most convenient form. Many metal hydrides react with water to generate the metal hydroxide and hydrogen. Two candidates were lithium hydride and magnesium hydride. What volume (in L) of gas is formed from 1.00 lb of each hydride reacting with excess water at 750. torr and 27°C?
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?
Consider the following balanced thermochemical equation for the decomposition of the mineral magnesite:
MgCO3 (s) ⟶ MgO (s) + CO2 (g) ΔH = 117.3 kJ
What is ΔH for the reverse reaction?
Lead can be prepared from galena [lead(II) sulfide] by first roasting the galena in oxygen gas to form lead(II) oxide and sulfur dioxide. Heating the metal oxide with more galena forms the molten metal and more sulfur dioxide.
(a) Write a balanced equation for each step.
Chromium(III) oxide reacts with hydrogen sulfide (H2S) gas to form chromium(III) sulfide and water:
Cr2O3(s) + 3H2S(g) ⟶Cr2S3(s) + 3H2O(l)
To produce 421 g of Cr2S3, how many moles of Cr2O3 are required?
Bismuth oxide reacts with carbon to form bismuth metal:
Bi 2O3(s) + 3C(s) ⟶2Bi(s) + 3CO(g)
When 0.607 mol of Bi2O3 reacts with excess carbon, how many grams of CO form?
How many grams of potassium chlorate decompose to potassium chloride and 638 mL of O2 at 128°C and 752 torr?
2 KClO3(s) ⟶2 KCl(s) + 3 O2(g)
Give the oxidation number of arsenic in the following:
Give the oxidation number of sulfur in each of the following:
A chloride of silicon contains 79.1 mass % Cl. If the molar mass is 269 g/mol, what is the molecular formula?
Calculate each of the following quantities:
Amount (mol) of solute in 145.6 L of 0.850 M sodium cyanide
How many total moles of ions are released when each of the following dissolves in water?
3.55×1019 formula units of LiCl
What monatomic ions would you expect potassium (Z = 19) and bromine (Z = 35) to form?
Calculate the following quantity:
Number of O atoms in 7.3×10−3 g of CaSO4·2H2O
The area of a telescope lens is 7903 mm 2. What is the area in square feet (ft 2)?