Question

For the reaction \[\ce{2A + B + C -> A2B + C}\], rate law has been determined to be, Rate = k [A] [B]². If the rate constant k = 2.0 × 10⁻⁶ mol⁻²Ls⁻¹, what will be the initial rate of the reaction with [A] = 0.1 mol L⁻¹, [B] = 0.2 mol L⁻¹ and [C = 0.8 mol L⁻¹?

Answer 1

Given:

k = 2.0 × 10⁻⁶ mol⁻²Ls⁻¹

[A] = 0.1 mol L⁻¹

[B] = 0.2 mol L⁻¹

[C] = 0.8 mol L⁻¹ (but not in the rate law, so it's irrelevant here)

Rate = k [A] [B]²

= 2.0 × 10⁻⁶ × (0.1) × (0.2)²

= 2.0 × 10⁻⁶ × 0.1 × 0.04

= 2.0 × 10⁻⁶ × 0.004

= 8.0 × 10⁻⁹ mol L⁻¹ s⁻¹

∴ The initial rate of the reaction is 8.0 × 10⁻⁹ mol L⁻¹ s⁻¹