For a reaction: aA → Products, [A]o -4.3 M, and the first two half-lives are 56 and 28 minutes, respectively. Calculate k (without units). Show Work! A. 7.7 x 10^-2
B. 4.2 x 10^-3
C. 3.8 x 10^-2
D. 8.3 x 10^-3
E. None of these​

C.

Explanation:

We are given that

Initial concentration,

First half life, minutes

Second half life, minutes

We have to find K.

The given reaction is zero order reaction.

We know that for zero order reaction

Using the formula

Hence, option C is correct.

answer; i believe the correct answer is (solid gold);

a 20-cm-long, cylindrical graphite (pure carbon) rod is inserted into an oxidizing atmosphere at 1145 k and 1.013 x 105 pa pressure. the oxidizing process is limited by the diffu- sion of oxygen counterflow to the carbon monoxide that is formed on the cylindrical surface.