For the reaction X + Y → Z, the reaction rate is found to depend only upon the concentration of X. A plot of 1/X verses time gives a straight line. What is the rate law for this reaction?

r = k [X]²

Explanation:

X + Y → Z

Generally, the rate of reaction depends on the concentration of reactants. However, the question stated that the rate depends only on reactant X.

The plot of 1/X versus time giving a straight line signifies that this is a second order reaction.

For a second-order reaction, a plot of the inverse of the concentration of a reactant versus time is a straight line with a slope of k.

From this, our rate law is r = k [X]²