**Q1: **

Consider the reaction between and at K. Under standard conditions, each species has a partial pressure of 1 atm. If a flask contains 0.500 atm of and 0.500 atm of , calculate the partial pressure of hydrogen at equilibrium.

- A 0.500 atm
- B atm
- C atm
- D atm
- E atm

**Q2: **

Nitrogen oxides are air pollutants produced by the reaction of nitrogen and oxygen at high temperatures. At , the value of the equilibrium constant for the reaction, , is . Calculate the equilibrium concentration of in air at if = 0.036 M and = 0.0089 M when equilibrium is reached.

- A 0.88 M
- B M
- C 0.78 M
- D M
- E M

**Q3: **

One of the important reactions in the formation of smog is represented by the equation: In a gas mixture, the initial partial pressures of and are both equal to atm. The partial pressures of all gases are 1.0 atm under standard conditions. Calculate the partial pressure of in the gas mixture at equilibrium.

- A atm
- B atm
- C atm
- D atm
- E atm

**Q4: **

What is the partial pressure of in an equilibrium mixture that results from the decomposition of with an initial pressure of 0.824 atm? Assume that all pressures in are expressed relative to a standard pressure of 1.00 atm and that changes in the pressure of are small enough to be neglected.

**Q5: **

Liquid is dark blue at low temperatures, but the color fades and becomes greenish at higher temperatures as the compound decomposes to and . At , a value of = 1.91 has been established for this decomposition. If 0.236 moles of are placed in a 1.52-L vessel at , what is the equilibrium partial pressure of ?

**Q6: **

What is the pressure of in an equilibrium mixture of , , and if the pressure of in this mixture is 0.115 atm and the pressure of is 0.450 atm?

- A atm
- B 20 atm
- C atm
- D atm
- E atm

**Q7: **

At and 1 atm, the partial pressures in an equilibrium mixture of and are = 0.70 atm and = 0.30 atm.

Nitrogen dioxide dimerizes to form dinitrogen tetroxide . How will the pressures of and change if the total pressure increases to 9.0 atm?

- AThe partial pressure of will increase, while that of will decrease.
- BBoth will decrease.
- CThe partial pressure of will decrease, while that of will increase.
- DBoth will increase.
- EThey will both stay the same.

Calculate to 1 significant figure the equilibrium partial pressure of at 9.0 atm and .

**Q8: **

What is the pressure of in an equilibrium gas mixture containing 0.45 atm of , 1.95 atm of , and 0.95 atm of at ?