What is plotted on the graph for a zero order reaction?

For a zero order reaction, the rate of the reaction is constant and does not depend on the concentration of the reactant. This characteristic leads to a straightforward relationship between concentration and time.

In a zero order reaction, the rate law can be expressed as:

[ \text{Rate} = k ]

where ( k ) is the rate constant. The integrated rate law for a zero order reaction shows that the concentration of the reactant decreases linearly over time:

[ [A] = [A]_0 - kt ]

In this equation, ( [A] ) is the concentration of the reactant at time ( t ), and ( [A]_0 ) is the initial concentration. When you rearrange this equation, it indicates that if you plot the concentration of the reactant against time, you will get a straight line with a slope of -k.

This linear behavior is what makes choice C the correct answer, as it correctly describes what is plotted for a zero order reaction. The other choices do not represent the correct relationship for zero order kinetics:

• Plotting ln[A] versus time (choice A) is characteristic of first order reactions.
• Plotting 1/[A] versus time (choice B