Reaction kinetics & Chemical equilibrium

In an energy profile, the activated complex is represented at the

• a. left end of the curve.

• b. right end of the curve.

• c. bottom of the curve.

• d. top of the curve.

Increasing the surface area of the reactants in a heterogeneous reaction

• a. tends to increase reaction rate.

• b. tends to decrease reaction rate.

• c. has no effect on reaction rate.

• d. cancels the rate-determining step.

The energy change,  $\Delta E$ , for a reaction is the energy difference between the

•  a. products and intermediates.  

•  b. products and reactants.  

•  c. products and the activated complex.  

•  d. reactants and intermediates.  

A substance that increases the rate of a chemical reaction without being consumed is a(n)

To be effective, a collision requires these two things: _________ and _________.

The activated complex is _________ in energy than the reactants.

If a collision between molecules is very gentle, the molecules are

• A. more likely to be oriented favorably.

• B. less likely to be oriented favorably.

• C. likely to react.

• D. likely to rebound without reacting.

A rate law relates

• A. reaction rate and temperature.

• B. reaction rate and concentration.

• C. temperature and concentration.

• D. energy and concentration.

A certain reaction is zero order in reactant A and second order in reactant B. What happens to the reaction rate when the concentrations of both reactants are doubled

• A. The reaction rate remains the same.

• B. The reaction increases by a factor of two.

• C. The reaction rate increases by a factor of four.

• D. The reaction rate increases by a factor of eight.

A chemical reaction is in equilibrium when

• A. forward and reverse reactions have ceased.

• B. the equilibrium constant equals 1.

• C. forward and reverse reaction rates are equal.

• D. No reactants remain.