Question

Partial Pressure and the Ideal Gas Law
Air is about 78.0% nitrogen molecules and 21.0% oxygen molecules. Several other gases make up the remaining 1% of air molecules.

Part A
What is the partial pressure of nitrogen in air at atmospheric pressure (1 atm)? Assume ideal behavior.
Express your answer to three significant figures and include the appropriate units.

Part C
What is the partial pressure of oxygen in air at atmospheric pressure (1 atm)? Assume ideal behavior.
Express your answer to two decimal places and include the appropriate units.

Answer 1

Charles's Law:
Part C
Refrigerators are usually kept at about 5∘C, while room temperature is about 20∘C. If you were to take an "empty" sealed 2-liter soda bottle at room temperature and place it in the fridge, would you expect it to contract to one-fourth its original volume?
Refrigerators are usually kept at about , while room temperature is about . If you were to take an "empty" sealed 2-liter soda bottle at room temperature and place it in the fridge, would you expect it to contract to one-fourth its original volume?

A: Yes, because 5 is one-fourth of 20.
B: No, because there is no gas inside the bottle.
C: No, because Celsius is not an absolute temperature scale.

Solution.

In accordance with Charles’s Law

T1 = 20°C = 293 K
T2 = 5°C = 278 K

So will be in 0.94 times less than

Answer: C.