Question

If the plot of log₁₀ [A] against t is a straight line with a negative slope, the reaction is of ______.

Options

• zero order

• first order

• second order

• third order

Answer 1

If the plot of log₁₀ [A] against t is a straight line with a negative slope, the reaction is of first order.

Explanation:

For a first-order reaction, the integrated rate law is:

log₁₀ [A] = `log_10 [A]_0 - k/2.303 t`

This is a straight-line equation with a negative slope when plotting log⁡₁₀ [A] vs t. The negative slope confirms first-order kinetics.