The activation energy is the ______________that the reactant(s) must acquire before reaching the transition state.

• A) threshold energy
• B) maximum energy
• C) constant energy
• D) critical energy

HCl is ________molecule.

• A) non-polar
• B) partially polar
• C) none of these
• D) highly polar

A reaction with a ________activation energy requires much more energy to reach the transition state.

• A) constant
• B) Large
• C) small
• D) negligible

Thermal energy relates direction to motion at the __________level.

• A) atomic
• B) none of these
• C) sub atomic
• D) Molecular

Which factor primarily influences the rate of a pseudo-first-order reaction?

• A) Catalyst concentration
• B) Concentration of the limiting reactant
• C) Nature of reactants
• D) Temperature

R is the real gas constant with value ________?

• A) 6.430 J/mol K.
• B) 9.614 J/mol K.
• C) 8.581 J/mol K.
• D) 8.314 J/mol K

For a zero-order reaction, how is the rate of the reaction affected when the concentration of the reactant is increased?

• A) Rate increases
• B) Rate remains constant
• C) Rate becomes zero
• D) Rate decreases

If the reaction proceeds faster by adding catalyst, the rate constant (k) _________?

• A) decreases
• B) remain unaffected
• C) Increases
• D) approaches zero

Half life of a first order reaction is ________of its initial concentration.

• A) directly proportional
• B) independent
• C) dependent
• D) inversely proportional

In the zero-order rate law equation, what does [A] represent?

• A) Time
• B) Initial concentration of the reactant
• C) Concentration of the reactant at any time t
• D) Rate constant

If the rate constant (k) for a zero-order reaction is 0.5 M/s and the initial concentration of the reactant is 1.0 M, what will be the rate of the reaction?

• A) 1.0 M/s
• B) 2.0 M/s
• C) 1.5 M/s
• D) 0.5 M/s

How is the graph of concentration against time for a zero-order reaction described?

• A) Parabolic
• B) Exponential
• C) No change in concentration with time
• D) Linear

In Arrhenius equation Ea is

• A) Access Energy
• B) Energy of Tolrance
• C) Activation Energy
• D) Zero Energy

In a chemical reaction, the transition state is defined as the _____________energy state of the system.

• A) lowest
• B) Highest
• C) Critical
• D) Constant

The Arrhenius equation can be used to determine the effect of a change of ____________on the rate constant.

• A) Temperature
• B) Pressure
• C) Initial concentration
• D) Concentration

Chemical reactions occur more rapidly at

• A) Lower Temperatures
• B) Lower Pressure
• C) Higher temperatures
• D) Higher pressure

Enzymes can be thought of as biological catalysts that __________activation energy.

• A) Lower
• B) maximize
• C) increase
• D) none of these

____________shows how the concentration of species changes over time.

• A) Integrated rate equation
• B) order of reaction
• C) mole fraction
• D) differential rate law

Activation enthalpy, ΔH‡, represents the difference in energy between the ground state and the ___________ in a chemical reaction.

• A) Final state
• B) none of these
• C) Critical state
• D) Transition state

In a pseudo-first-order reaction, if the concentration of the excess reactant is doubled, how does this affect the reaction rate?

• A) The reaction rate remains unchanged
• B) The reaction rate increases linearly
• C) The reaction rate doubles
• D) The reaction rate quadruples