1. Oxygen is 101 kPa; hydrogen is 505 kPa
All the oxygen gas from a 10.0-L container at a pressure of 202 kPa is added to a 20.0-L container of hydrogen at a pressure of 505 kPa. After the transfer, what are the partial pressures of oxygen and hydrogen?
Oxygen is 101 kPa; hydrogen is 505 kPa
Oxygen is 202 kPa; hydrogen is 505 kPa
Oxygen is 101 kPa; hydrogen is 253 kPa
Oxygen is 202 kPa; hydrogen is 253 kPa

2. Nitrogen monoxide and oxygen gas combine to form the brown gas nitrogen dioxide, which contributes to photochemical smog. How many liters of nitrogen dioxide are produced when 34 L of oxygen reacts with an excess of nitrogen monoxide? Assume conditions of STP.
34 L O2 x 1 mol O2 x 2 mol NO2 x L NO2 =
22.4 L O mol O mol NO2
= 68 L NO2
3.0 L NO2
138 L NO2
68 L NO2
22.4 L NO2
2 NO2 (g) + O2 (g) → NO2 (g)

3. trigonal pyramid P4 (s) + 6H2 (g) → 4PH3 (g) 0.42 L PH3 0.28 L PH3
Phosphorus and hydrogen can be combined to form phosphine. How many liters of phosphine are formed when 0.42 L of hydrogen reacts with phosphorus at STP?
P4 (s) + 6H2 (g) → 4PH3 (g)
trigonal pyramid
0.42 L PH3
0.28 L PH3
1.68 L PH3
22.4 L PH3

4. Which of the following is not characteristic of matter in the gaseous state?
Gases fill their containers completely.
The collisions particles undergo with the container walls exert pressure.
Gases have mass.
The pressure of a gas is independent of its temperature.
Gases are compressible.
The distances between gas particles is relatively large.

5. False ... just the opposite!
Gases behave most ideally at high pressures and low temperatures.

6. Which of the following changes would increase the pressure of a gas in a closed container? I Part of the gas is removed. II The container size is decreased. III Temperature is increased.
I & II only
II & III only
I & III only
I, II & III
none of the above

7. Which of the following changes would increase the pressure of a gas in a closed container? I Part of the gas is removed. II The container size is decreased. III Temperature is increased.
I & II only
II & III only
I & III only
I, II & III
none of the above