SAT Chemistry Practice Paper 21

SAT Chemistry Practice Paper 21
SET 1

1. HCN(aq) → H+(aq) + CN–(aq)

Hydrocyanic acid dissociates according to the reaction given above. Which of the following expressions is
equal to the acid dissociation constant for HCN?

A. [H+][CN-]

B. [H+][CN-][HCN]



C.



D.



E.

2. The reaction progress diagram of an uncatalyzed reaction is shown by the solid line. Which dotted line
presents the same reaction in the presence of a catalyst?




A.

B.

C.

D.

E.

3. In a hydrogen atom, when an electron jumps from an excited energy state to a more stable energy
state,

, A. electromagnetic radiation is emitted by the atom

B. electromagnetic radiation is absorbed by the atom

C. the atom becomes a positively charged ion

D. the atom becomes a negatively charged ion

E. the atom undergoes nuclear decay

4. A closed 5-liter vessel contains a sample of neon gas. The temperature inside the container is 25°C,
and the pressure is 1.5 atmospheres. (The gas constant, R, is equal to 0.08 L?atm/mol?K.)

Which of the following expressions is equal to the molar quantity of gas in the sample?



A.



B.



C.



D.



E.

5. A closed 5-liter vessel contains a sample of neon gas. The temperature inside the container is 25°C,
and the pressure is 1.5 atmospheres. (The gas constant, R, is equal to 0.08 L?atm/mol?K.)

If the neon gas in the vessel is replaced with an equal molar quantity of helium gas, which of the following
properties of the gas in the container will be changed?

I. Pressure

II. Temperature

III. Density

A. I only

B. II only

C. III only

D. I and II only

E. II and III only