Question

The slope of a graph, log [A]_t versus 't' for a first order reaction is −2.5 × 10⁻³ s⁻¹. The rate constant for the reaction is ____________.

Options

• −2.5 × 10⁻³ s⁻¹

• 2.5 × 10⁻³ s⁻¹

• 1.086 × 10⁻³ s⁻¹

• 5.757 × 10⁻³ s⁻¹

Answer 1

The slope of a graph, log [A]_t versus 't' for a first order reaction is −2.5 × 10⁻³ s⁻¹. The rate constant for the reaction is 5.757 × 10⁻³ s⁻¹.

Explanation:

The slope of a graph, log[A]_t versus 't' for a first order reaction is given by

Slope = `-"k"/2.303`

−2.5 × 10⁻³ × 2.303 = −k

∴ k = 5.757 × 10⁻³ s⁻¹