# Worksheet: First-Order Rate Plots

In this worksheet, we will practice plotting concentration–time data for first-order reactions to calculate the rate constants and initial concentrations.

Q1:

During a reaction, the concentration of a reactant is measured as a function of the reaction time, . All other reactants are in large excess. Which graph could be plotted to check whether the reaction is of the first order with respect to ?

• A against
• B against
• C against
• D against
• E against

Q2:

The concentration of a reactant A was monitored during the course of a reaction. The data were plotted on a graph of against time. If the reaction is first order with respect to A, what is the initial concentration of A in terms of the gradient of the plot and the -intercept ?

• A
• B
• C
• D
• E

Q3:

The concentration of a reactant A was monitored during the course of a reaction. The data were plotted on a graph of against time. If the reaction is first order with respect to A, what is the rate constant of the reaction in terms of the gradient of the plot and the -intercept ?

• A
• B
• C
• D
• E

Q4:

Compounds A and B react according to the following equation. The reaction is first order with respect to A, and B is in large excess. Which function of the reaction rate varies linearly with the reaction time?

• A
• B
• C
• D
• E