ChemComm: Unit 10 Gas Laws Name:Period:

10.9 REVIEW – Gas LawsComplete the following question using your knowledge of gas laws and gas properties.

1. What is pressure?

Pressure is force divided by area

2. Heavy vehicles that must move easily over loose sand are often equipped with special tires.

a. Would you expect these tires to be wide or narrow?

The tires should be wide in order to spread the force out over a greater area

b. Explain your answer using the concept of pressure.

Wide tires spread out the force of the car on the sand therefore there would be a lower amount of pressure

3. Explain why a sealed bag of potato chips “puffs out” (increase and volume) when it is carried from sea level up to a high mountain pass.

When a bag is sealed at sea level, the internal pressure is greater than the outside pressure of the mountain pass, making the bag puff out.

4. A student uses a spray can containing compressed nitrogen gas to clean her computer circuit board. Remember: Nitrogen gas is a diatomic molecule (N2). Draw pictures of the gas molecules as they would appear (use 10 molecules of N2):

5. Communicate the relationship between volume and pressure of a gas graphically (sketch a graph, left) and verbally (write a few sentences, right):

As the pressure goes up, the volume of a gas goes down assuming the temperature is constant

6. The volume of a container is halved by pushing down the attached piston. What will happen to the pressure, if temperature remains constant?

The pressure will double

7. Calculate the new volume of a 7.0 L balloon if the pressure is reduced from 1.0 atmosphere to 0.80 atmosphere (assume the temperature remains constant).

8. Use kinetic molecular theory to explain Charles’ Law.

As the temperature of a gas increases, the molecules move faster and the space between the molecules increase. This causes the volume to increase.

9. What is the new volume of a 7.0 L balloon when it is brought from a location where the temperature is 30°C to a location where the temperature is 25°C (pressure remains unchanged to 1.0 atmosphere)?

10. Communicate the relationship between pressure and temperature of a gas graphically (sketch a graph, left) and verbally (write a sentence).

11. How would an increase in the temperature of a gas stored in a rigid metal container impact the pressure of that gas? The pressure of the gas would increase

12. Solve for the unknown variable in each scenario using your knowledge of the gas laws. It may be necessary to convert some temperatures to Kelvin. If a box is shaded, that variable is considered to be a constant in the given scenario.

P1 V1 T1 P2 V2 T2

Latex Balloon ? 22°C 3.40 L 51°C

Used Tire 30 psi 20 °C 38 psi ?

Weather balloon 104 kPa 1350 L ? 1400L

13. Balance the following chemical reaction, and then determine how many liters of N2 are necessary to react with 5 liters of O2?

a. _____ N2 + __2__O2 __2__ NO2

14. What volume would 10.0 grams of gaseous CO2 occupy at STP?

15. Determine the pressure exerted by 0.25 mole neon gas in a 2.75 L container at 35 °C.

16. What pressure will 4.5 mol of gas exert, if the gas occupies a 10.0 L container at a temperature -20°C?

17. At what temperature will 2.5 mol of nitrogen gas exert a pressure of 10.0 atm in a 2.0 L container?