Question

A first order reaction is found to have a rate constant, k = 5.5 × 10-14 s-1. find the half-life of the reaction

Answer 1

Answer:

the half-life of rxn is 12.6×10raised power -12

Answer 2

Answer:

The Correct Answer would be 12.6×10¹² sec. Half-life of the reaction having rate constant as k = 5.5×10⁻¹⁴ sec⁻¹ would be 12.6×10¹² sec.

Explanation:

The half-life of a reaction, t₁₂, is the amount of time required for a reactant to decrease it's concentration by half when compared to its initial concentration. The half-life of reaction application is basically used in chemistry as well as in medicinal field to predict the concentration of several substances over time.

Now, based on the order of reaction, formula for calculating half-life are different. For first order, it is:

             t₁₂ = 0.693/k      (where, k = rate constant of first order reaction)

Hence,

           

               t₁₂ = 0.693 / 5.5×10⁻¹⁴

                    = 0.126×10¹⁴

              t₁₂ = 12.6×10¹² sec

Hence, half-life of reaction would be 12.6×10¹² sec.