Name: _______________________
December 2014
Gr.11 Chemistry Unit 4 Test: Gases and the Atmosphere
Part A: Multiple Choice (18 marks)
Circle the letter of the best answer.
1. The layer of the Earth’s atmosphere that humans live in is called the:
a. ionosphere
b. troposphere
c. exosphere
d. thermosphere
e. stratosphere
2. The layer of Earth’s atmosphere that reaches the highest temperatures is called
the:
a. ionosphere
b. troposphere
c. exosphere
d. thermosphere
e. stratosphere
3. In the equation for Boyle’s Law, P1 stands for:
a.
b.
c.
d.
new pressure
standard pressure, 1 atm
difference in pressure
original pressure
4. When the volume of a gas is doubled, what happens to its temperature
(assuming constant pressure)?
a.
b.
c.
d.
doubles
stays the same
reduced to half
rises, then falls
5. Who was the scientist who developed the first mercury barometer:
a.
b.
c.
d.
Torricelli
Von Guericke
Galileo
Pascal
6. Who was the first scientist to develop the suction pump:
a.
b.
c.
d.
Boyle
Galileo
Torricelli
Pascal
7. If the temperature of a gas decreases, what happens to its pressure?
a.
b.
c.
d.
increases
stays the same
decreases
increases then decreases
8. The mathematical statement of Charles’ Law is
a.
b.
c.
d.
V1 T1= V2 T2
V1 T 2 = V 2 T 1
P1T2 = P2T1
P1T1 = P2T2
9. The equation P1V1 = P2V2 is known as:
a.
b.
c.
d.
e.
the Combined Gas Law
Boyle's Law
Charles' Law
Guy-Lussac’s Law
the Ideal Gas Law
10. Which value represents standard temperature?
a.
b.
c.
d.
e.
273ºC
373 K
-273°C
0K
273 K
11. Which value represents standard pressure?
a.
b.
c.
d.
e.
101.3 Pa
101.3 PSI
760 mm Hg
760 atm
14.7 Torr
12. What will happen if we cool a 20 L sample of gas from 313 K to 273 K?
a.
b.
c.
d.
The volume of gas increases.
The number of moles of gas increases.
The volume of gas decreases.
The number of moles of gas decreases.
13. The following is the only gas law that is NOT a direct relationship:
a.
b.
c.
d.
Charles’ Law
Combined Gas Law
Boyle’s Law
Torricelli’s Law
14. 1.00 atm is equivalent to:
a.
b.
c.
d.
101.3 Pa or 14.7 PSI
101.3 Pa or 760 mm Hg
101.3 kPa or 14.7 PSI
101.3 Pa or 760 mm Hg
15. What is 780.0 mm Hg equivalent to:
a.
b.
c.
d.
1 atm
1.026 atm
0.974 atm
0.00132 atm
16. If a balloon at 55.0 ºC has a volume of 0.500 L, what will be its new volume if
cooled down to 20.0 ºC, assuming constant pressure?
a.
b.
c.
d.
182 ml
1375 ml
447 ml
560 ml
17. If a syringe filled with air has a volume of 25.00 ml at normal atmospheric
pressure at 25.0 ºC, what will be its new volume at 29.4 PSI and 35.0 ºC?
a.
b.
c.
d.
23.3 ml
12.9 ml
17.5 ml
23 ml
18. A sample of carbon dioxide at 70 ºC and 1.45 atm. What is the new pressure of
the gas at 35 ºC if the volume remains constant?
a.
b.
c.
d.
1.61 atm
2.90 atm
1.30 atm
0.725 atm
Part B: Short Answer (22 marks)
19. (1) Sketch a graph showing what the variation of temperature with volume at a
constant pressure would look like below:
20. (3) What is the new pressure of a fixed volume of a gas if initial conditions are at
STP and the temperature is increased to 50°C?
21. (3) If you begin with a 6.45 L sample of a gas at standard temperature and
pressure, and increase the pressure to 135.4 kPa under a constant temperature,
what is the new volume?
22. (3) If you have 25.0 L of a gas at- 30ºC held at a constant pressure, what is the
new volume at 20ºC? Show your work.
23. (3) If 4.50 L of a gas are at 25.0ºC and 1.25 atm, what would be the new
temperature if the volume was decreased to 2.50 L and the pressure was
increased to 2.00 atm? Show your work.
24. (3) What is the pressure of 3.50 moles of oxygen gas that has a volume of
65.4 L at 15°C?
25. (4) A 30.0 g sample of carbon dioxide gas, CO2, has a volume of 25.0 L at
25.0ºC. Calculate the pressure. Show your work.
26. (2) Explain why water boils at a lower temperature at a higher elevation.
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