In first order reaction, 20 % concentration remains after 10 min. What would be the rate constant of reaction if ₁₀(5) = 0.6989 ?

Step-by-step solution

For a first order reaction, the rate constant k is given by the formula: k = 2.303 t ₁₀ ( [A]₀ [A]_t ) Given that 20 % concentration remains after 10 min, we have: t = 10 min [A]_t = 20 100 [A]₀ = 0.2 [A]₀ Substituting these values into the formula: k = 2.303 10 ₁₀ ( [A]₀ 0.2 [A]₀ ) k = 2.303 10 ₁₀(5) Given ₁₀(5) = 0.6989 : k = 2.303 10 0.6989 k = 0.2303 0.6989 k = 0.1609 min ⁻¹