Download Review Chapters 13-17

Chemistry B2A
Chapters 13-17 review
1. A balloon contains 4 moles of an ideal gas with a volume of 5.0 L. If an additional 8 moles
of the gas is added at constant pressure and temperature, what will be the final volume of the
balloon?
2. If 2.6 moles of nitrogen gas are confined to a 6.0 L vessel at 177 °C and 12.0 atm. If the
vessel is allowed to expand isothermically (constant temperature) to 36.0 L, what would be
the final pressure?
3. How many grams of nitrogen will occupy a 7.5 liter container at STP?
4. Suppose you have 56g of ammonia gas (NH3) at 264°F, occupying a container which is
500. mL in size. What is the pressure of this gas in atmospheres?
5. When sodium bicarbonate, NaHCO3(s), is heated. Sodium carbonate (Na2CO3) is produced,
with the evaluation of water vapor and carbon dioxide gas.
2NaHCO3(s) → Na2CO3(s) + H2O(l) + CO2(g)
What total volume of gas, measured at 29°C and 769 torr, is produced when 1.50g of
NaHCO3(s) is completely converted to Na2CO3(s)?
Dr. Behrang Madani
Chemistry B2A
Bakersfield College
6. Suppose that 4.18g of oxygen gas and 3.68g of nitrogen gas are confined in a 11.3-L
container at 36°C. What would be the pressure of container? Calculate the partial pressure of
each gas in this mixture.
7. A 650.-mL sample of O2 gas at 25°C was prepared by decomposing a 4% aqueous solution
of hydrogen peroxide (H2O2):
2H2O2(aq) → 2H2O(g) + O2(g)
The oxygen thus prepared was collected by displacement of water. The total pressure of gas
collected was 862 mm Hg. What is the partial pressure of O2 in the mixture? How many
moles of O2 are in the mixture? (The vapor pressure of water at 25°C is 23.8 mm Hg).
8. If 5.2L of argon gas at 56°C and 1.2atm is mixed with 32L of propane gas (C3H8) at 56°C
at 1.2atm in a 12L tank. Calculate the partial pressure of each gas and total pressure in the
tank at 56°C.
9. Which substance in each pair has the largest vapor pressure at a given temperature?
a) NH3 or PCl3
b) CH3CH2OH or CH3CH2CH2CH3
c) CO2 or HBr
Dr. Behrang Madani
Chemistry B2A
Bakersfield College
10. Arrange these compounds in each set in order of increasing boiling points:
a) CCl4, Mg(OH)2, CH3OH, H2S
CH3
b) CH3-CH2-CH3, CH3-CH2-CH2-CH3, CH3-CH2-CH2-CH2-OH, CH3-C-OH
CH3
11. How much heat is released (in kJ) when 105.0 g of steam at 100.0 °C is cooled to ice at
-15.0 °C?
Enthalpy of vaporization of water = 40.67 kJ/mol
Enthalpy of fusion for water = 6.01 kJ/mol
molar heat capacity of liquid water = 4.18 J g-1 °C-1
molar heat capacity of ice = 2.02 J g-1 °C-1
12. Calculate the energy (in kJ) required to heat 67g of potassium metal at 12°C to liquid at
120°C. (molar heat of fusion is 2.334 kJ/mol, specific heat of liquid potassium is .., specific
heat of the solid is 0.75 J/g°C). The melting point of potassium is 63.38°C.
13. How much KBr must be used to prepare 250mL of 4.4%(w/v) solution?
14. If a solution is prepared by dissolving 7.7g of lithium iodide, in enough water to make
400mL of solution, what is the %(w/v) of LiI?
Dr. Behrang Madani
Chemistry B2A
Bakersfield College
15. What is the weight of BaCl2 in a 250 mL bottle of 0.23M BaCl2?
16. Assuming that the volumes are additive, what volume of water must be added to 35mL of
12M HCl to make a solution which is 3.4M?
17. How do we prepare 3.9L of a 0.012M aqueous solution of NaHSO3?
18. What mass of sulfuric acid would be needed to precipitate the barium ion from 45 mL of
0.121 M BaCl2 solution?
BaCl2(aq) + H2SO4(aq) → BaSO4(s) + 2HCl(aq)
19. In questtion18, how many grams of barium sulfate form when a 2.3 g of BaCl2 is added to
56 mL of 0.51 M H2SO4 solution?
20. A sodium hydroxide solution has a pH of 10.40. What is the [H+], [OH-], and pOH?
Dr. Behrang Madani
Chemistry B2A
Bakersfield College
21. If 33.2 mL of an aqueous solution of HCl requires 52 mL of 0.74 M NaOH to reach the
end point, what is the molarity of the HCl solution?
22. If 54 mL of an aqueous solution of H3PO4 requires 34 mL of 0.83 M NaOH to reach the
end point, what is the molarity of the H3PO4 solution?
23. For each of following solutions, calculate the normality.
a) 0.986M H3PO4
b) 68.9mL of 0.23M Mg(OH)2 diluted with water to a total volume of 252mL.
c) 43.2mg of H2CO3; 231mL
24. Show the acid, base, conjugate acid and conjugate base in following reactions:
a) H2SO4 + Mg(OH)2 → MgSO4 + 2H2O
b) HNO3 + NH3 → NH4+ + NO3-
Dr. Behrang Madani
Chemistry B2A
Bakersfield College
25. Write the formula for the conjugate base of each acid.
a) H2SO4
b) H3BO3
c) HI
d) H3O+
e) NH4+
f) HPO42-
26. What is the molarity of a solution made by dissolving 9.1 g of H3PO4 in enough water to
make 22.3 L of solution? Assume that H3PO4 ionizes completely in water to H+ and PO43ions. What is the normality and pH of the solution? Find the concentration of OH-?
27. Write the equilibrium expression for the follwoing equations:
a) H2(g) + Br2(g) ↔ 2 HBr(g)
b) 2HCl(g) ↔ H2(g) + Cl2(g)
c) 2Mg(s) + O2(g) ↔ 2MgO(s)
d) CH4(g) + 4Cl2(g) ↔ CCl4(l) + 4 HCl(g)
28. Consider the quilibrium N2(g) + 3H2(g) ↔ 2NH3(g) at a certain temperature. An
equilibrium mixture in a 4.00 liter vessel contains 1.60 moles NH3, 0.800 moles N2, and 1.20
moles H2. What is the value of K?
Dr. Behrang Madani
Chemistry B2A
Bakersfield College
29) Consider the reaction:
4HCl(aq) + MnO2(s) + Heat ↔ Cl2(g) + 2H2O(l) + MnCl2(aq)
In which direction (right or left) will the equilibrium position shift with the following
changes?
a) If a catalyst is added.
b) If pressure is lowered.
c) If temperature is lowered.
d) If H2O(l) is added.
e) If MnCl2 is removed.
30. The Ksp value for solid Al(OH)3 is 3.7×10-15 at 25°C. Calculate the solubility of Al(OH)3
in water at 25°C.
31. Approximately 0.14 g of nickel(II) hydroxide, Ni(OH)2(s), dissolves per liter of water at
20°C. Assume that Ni(OH)2 ionizes completely in water to Ni2+ and OH- ions. Calculate Ksp
for Ni(OH)2(s) at this temperature.
Dr. Behrang Madani
Chemistry B2A
Bakersfield College