The decomposition of a to b is a first-order reaction with a half-life of 14.2 min: a → 2b if the initial concentration of a is 0.304 m, how long will it take for the concentration of a to decrease by 43.0 %?

It take 16.9 min for the concentration of A to decrease by 43.0 %

Explanation:

The first-order reaction law is

And the half-life time for the first-order reaction is

- [A] is the concentration of the reactant at any time (t) of the reaction

- [A]0 is the concentration of the reactant at the beginning of the reaction

- k is the rate constant.  

- t1/2 is the half-life time

Thus, for this reaction k is

Decreasing the concentration of the reactant by 43.0% means the concentration of A (reactant) at the end of the reaction has to be:  

Replacing [A] in the equation of the law  

Clearing the t  

Replaicing with [A]0 = 0.304M and k = 0.05min-1

the electrical  conductivity  of asolution  of an electrolyte is measured by determining the resistance of thesolution  between two flat or cylindrical electrodes separated by a fixed distance.

b. accuracy of the data matters alot more than its number of digits, organization or amount of detail. quantitative observation is more accepted than the qualitative observation.