AP Chemistry Unit 5 Review

Front

What is a first order reaction?

Back

A first order reaction is a reaction whose rate is directly proportional to the concentration of one reactant. The rate constant (k) remains constant, while the rate decreases as the reactant is consumed.

Front

How does the rate constant (k) behave in a first order reaction?

Back

In a first order reaction, the rate constant (k) remains the same throughout the reaction, regardless of the concentration of the reactants.

Front

What is the relationship between concentration and rate in a first order reaction?

Back

As the concentration of the reactant decreases, the rate of the reaction also decreases.

Front

What is the formula for calculating the rate of a first order reaction?

Back

The rate of a first order reaction is given by the equation: rate = k[A], where [A] is the concentration of the reactant.

Front

How do you calculate the time it takes for a reactant to decrease in concentration in a first order reaction?

Back

Use the formula: t = (1/k) * ln([A]0/[A]), where [A]0 is the initial concentration and [A] is the final concentration.

Front

What is the role of a catalyst in a chemical reaction?

Back

A catalyst lowers the activation energy required for a reaction, thereby increasing the rate of the reaction without being consumed in the process.

Front

What is the effect of a catalyst on the energy profile of a reaction?

Back

A catalyst lowers the amount of energy added to a reaction, making it easier for the reaction to occur.

Front

What is a reaction mechanism?

Back

A reaction mechanism is a step-by-step description of the pathway taken by reactants to form products, including all intermediate species.

Front

What is the rate law for a reaction?

Back

The rate law expresses the relationship between the rate of a reaction and the concentration of its reactants, typically in the form: Rate = k[A]^n[B]^m.

Front

How are the exponents in a rate law determined?

Back

The exponents n and m in a rate law are determined experimentally, not from the balanced chemical equation.