General Chemistry - Chemical Kinetics

These flashcards are designed to help students review key concepts from their General Chemistry lecture on chemical kinetics, focusing on reaction rates, rate laws, and the influence of concentration and catalysts on chemical reactions.

What is the study of rates at which reactants/products change during a reaction called?

Chemical Kinetics.

What is defined as the change in concentration of a reactant or product over time?

Reaction Rate.

What happens to the reaction rate if the concentration of reactants increases?

The reaction rate increases.

What is the average rate of a reaction?

Change in concentration of reactant or product over a specific time interval.

How is the instantaneous rate determined?

It is determined graphically as the tangential slope of the concentration vs time plot.

What does the rate law relate reaction rate to?

It relates reaction rate to the concentrations of reactants and catalysts raised to various powers.

What does a zero-order reaction imply about the effect of concentration on reaction rate?

There is no effect on the reaction rate.

How are the orders of a reaction determined?

They must be determined experimentally.

What is the Arrhenius equation used for?

It is used to determine the rate constant and activation energy of a reaction.

What types of reactions do catalysts increase the rate of?

Both homogeneous and heterogeneous reactions.

What is meant by the term 'rate-determining step'?

It is the slowest elementary reaction that determines the overall rate of the reaction.

What type of reaction order is indicated if doubling the concentration of a reactant results in quadrupling the reaction rate?

It indicates a second-order reaction.

How do you calculate the half-life of a first-order reaction?

Half-life = 0.693/k.

What does the potential energy diagram illustrate in terms of reaction?

It illustrates the energy changes during a reaction, indicating whether it is exothermic or endothermic.

What is the role of an enzyme in a reaction?

Enzymes act as catalysts, increasing the rate of reaction without being consumed.

How do you express the units for the rate constant (k) of a second-order reaction?

Rate = M^-1 · s^-1.

What does the transition state refer to in a reaction?

It refers to the high-energy state that is formed during the transformation of reactants to products.

When determining the reaction order, what must remain constant?

All but one initial concentration must remain constant.

What is indicated if the rate of a reaction is doubled when the concentration of a reactant is doubled?

It indicates that the reaction is first order with respect to that reactant.

What is a characteristic of catalysts in a chemical reaction?

They change the reaction rate but are not consumed in the overall reaction.

What is the significance of molecularity in reaction mechanisms?

It refers to the number of reactant particles involved in an elementary step.

What do you determine from temperature dependence of rate constants?

You can determine the activation energy (Ea).