# 11.E: Exercises

## 11.5: Applications of the Ideal Gas Law: Molar Volume, Density and Molar Mass of a Gas

1. If 100 mL of $$\ce{HCl}$$ gas at 300 K and 100 kPa dissolves in 20 mL of pure water, what is the concentration?

Hint: 0.4 mol/L

Skill:
Calculate n using ideal gas law.

2. If 100 mL of $$\ce{HCl}$$ gas at 300 K and 100 kPa dissolved in pure water requires 12.50 mL of the $$\ce{NaOH}$$ solution to neutralize in a titration experiment, what is the concentration of the $$\ce{NaOH}$$ solution?
Hint: 0.32 mol/L

Skill:
Apply ideal gas law to solve stoichiometry problems.

3. If 100 mL of $$\ce{HCl}$$ gas at 300 K and 200 kPa dissolved in pure water requires 12.50 mL of the $$\ce{NaOH}$$ solution to neutralize in a titration experiment, what is the concentration of the $$\ce{NaOH}$$ solution?

Hint: 0.64 mol/L

Skill:
Solve stoichiometric problem.

4. Hydrogen sulfide reacts with sulfur dioxide to give $$\ce{H2O}$$ and $$\ce{S}$$,

$$\ce{H2S + SO2 \rightarrow H2O + S_{(solid)}}$$, unbalanced

If 3.0 L of $$\ce{H2S}$$ gas at 760 torr produced 4.8 g of sulfur, calculate the temperature in C.

Hint: 93 degrees C

Skill:
Apply ideal gas law to solve stoichiometry problems.

5. When 10.0 mL of $$\ce{AgNO3}$$ solution is treated with excess amount of $$\ce{HI}$$ gas to give 0.235 g of $$\ce{AgI}$$, what is the concentration of the $$\ce{AgNO3}$$ solution?

Hint: 0.10 M

6. When an $$\ce{AgNO3}$$ solution is treated with 50.0 mL of $$\ce{HI}$$ gas to give 0.235 g of $$\ce{AgI}$$, what is the concentration of the $$\ce{HI}$$ gas?

Hint: 0.020 mol/L

7. When an $$\ce{AgNO3}$$ solution is treated with 50.0 mL of $$\ce{HI}$$ gas at 300 K to give 0.235 g of $$\ce{AgI}$$, what is the pressure of the $$\ce{HI}$$ gas?

Hint: 0.49 atm

Discussion:
Depending on the numerical values you use, you may get the pressure in other units.

8. When an $$\ce{AgNO3}$$ solution is treated with 50.0 mL of $$\ce{HI}$$ gas at 374 torr to give 0.235 g of $$\ce{AgI}$$, what is the temperature of the $$\ce{HI}$$ gas?

Hint: 300 K

Discussion:
Note the relationship of this problem with the previous one.