Chemistry Answers

A 1.00 L flask contains 2.073 g O2 and 20.13 g N2 at 25.0°C. What is the total pressure? [1] 0.856 atm

[2] 1.09 atm

[3] 19.2 atm

[4] 22.2 atm

[5] None of the above 

For a gas, which two variables are inversely proportional to each other (if all other conditions remain constant)?

[1] Pressure and temperature

[2] Pressure and volume

[3] Volume and temperature

[4] Amount (number of moles) and volume

[5] Pressure, temperature and volume 

A 3.20 mol sample of a gas occupies a volume of 350 mL at 300.0 K. What is its pressure?

[1] 1.32 atm

[2] 67.0 atm

[3] 184 atm

[4] 225 atm

5] 312 atm 

What is the partial pressure of oxygen in a container that contains 2.0 mol of oxygen, 3.0 mol of nitrogen, and 1.0 mol of carbon dioxide when the total pressure is 900 Torr?

[1] 100 Torr

[2] 200 Torr

[3] 300 Torr

[4] 400 Torr

[5] None of the above

The properties of a real gas are most likely to deviate from those properties predicted for an ideal gas when

[1] the pressure is low

[2] the temperature is high

[3] the pressure is high and the temperature is low

[4] the pressure is low and the temperature is high

[5] it is a diatomic gas

Consider the reaction: H2 (g) + Br2 (g) ⇆ 2HBr (g

Suppose that the value of the equilibrium constant is very large, which species will predominate at equilibrium?

[1] H2

[2] Br2

[3] HBr

[4] Both H2 and Br2

[5] All species will have the same concentration.

The expression for Kc for this reaction is:

[1] Kc= [H2][Br2] / [HBr]2

[2] Kc= [H2][Br2] / [HBr]

[3] Kc= [HBr]2 / [H2][Br2]

[4] Kc= 2[HBr] / [H2][Br2]

[5] Kc= [HBr] / [H2][Br2]

According to Le Chatelier’s principle, which of the following will not affect the position of a chemical equilibrium?

[1] Changing the temperature

[2] Adding a catalyst

[3] Changing the volume

[4] Changing the concentration of the products

[5] None of the above 

Atmospheric pressure on the peak of Kilimanjaro can be as low as

0.20 atm. If the volume of an oxygen tank is 10.0L, at what

pressure must the tank be filled so the gas inside would occupy a

volume of 1.2 x 103L at this pressure?

An aqueous solution of HCl is added to an aqueous solution of Ca(OH) 2 and a reaction occurs. 8.9x10 -

6 mol of (OH – ) ions are measured in the 750mL solution. Remember, Molarity = mol/L. Calculate the

concentration of the H + ions. Is the solution more acidic or basic?