Chemistry and Gases Practice Questions

Review the following concepts if needed -  Chemistry and Gases Study Guide

Practice Questions

Convert the following (problems 1-3) using the correct number of significant figures.

1. 560 mm Hg to atm

2. 1.23 atm to pascals

3. 2.3 atm to torr

4. A child releases a 2.5 L helium balloon that has an internal pressure of 3.4 atm. If a constant temperature is assumed, at what pressure will the balloon be 3.0 L?

5. A 25.0 L beach ball at 760 mm Hg and 25° C is put into a tank of liquid nitrogen at – 196° C. What will be the size of the beach ball if the pressure remains constant?

6. At the start of a trip, an automobile tire's pressure reads 32 psi at 25° C. What will be the pressure if friction heats up the tire to 50° C (assume any volume change is negligible)?

7. How many moles are in a sample of a 50.0 L tank of propane gas at 25° C and 5.60 atm?

8. What is the density of a sample of helium gas at 200° C and 760 mm Hg?

9. An amount of 2.0 g of dry ice (CO₂) is added to an empty balloon. After the dry ice completely sublimes to a gas at 1.0 atm and 25° C, what will be the volume of the balloon?

10. An empty 2.5 L diving tank is filled with 1.0 mole of helium and 0.25 moles of oxygen at 25° C. Calculate the total pressure of the tank. (Hint: Use the ideal gas law to calculate the partial pressures.)

11. If the barometer reads 751 mm Hg, what are the partial pressures of oxygen and nitrogen in the atmosphere?

12. Oxygen and nitrogen are the two major components of the atmosphere. What is the diffusion ratio for oxygen versus nitrogen?

 Answers