1. If 3.0 liters of oxygen gas react with excess carbon monoxide at STP, how many liters of carbon dioxide can be produced under the same conditions? 

2 CO _(g) + O_{2 (g)} ____ 2 CO_{2 (g)}

_{a) 1. L} 

_{b) 3.0 L} 

c) 4.5 L

d) 6.0 L

2. Under certain conditions argon (Ar) gas diffuses at a rate of 3.2 centimeters per second. Under the same conditions, an unknown gas diffuses at a rate of 4.5 centimeters per second. What is the approximate molar mass of the unknown gas?

a) 10 g/mol

b) 20 g/mol

c) 28 g/mol

d) 56 g/mol

3. Which of the following gases effuses the fastest at a given temperature?

a) Ne

b) CH4

c) Ar

d) H2

4. What is the volume of 3.5 moles of oxygen gas (O₂) at standard temperature and pressure (STP)?

a) 6.4 L

b) 22.4 L

c) 32.0 L

d) 78.4 L