Question

The formation of tert-butanol is described by the following chemical equation: (CH3), CBr (aq) + OH(aq) → Br" (aq) +(CH), COH(aq)
Suppose a two-step mechanism is proposed for this reaction, beginning with this elementary reaction: (CH3), CBr (aq) → (CH3),c* (aq) + Br" (ag)

Suppose also that the second step of the mechanism should be bimolecular.

Suggest a reasonable second step.

That is, write the balanced chemical equation of a bimolecular elementary reaction that would proposed mechanism. X 5 ?

Answer 1

Answer:

$(CH_3)_3С^+ (aq) + OH^- (aq)\rightarrow (CH_3)_3COH (aq)$

Explanation:

There are two ways of looking at this problem. The first way, slightly more advanced, is to understand that the carbocation formed is an intermediate in this reaction: it is formed in one step and consumed in the subsequent step.

Secondly, we have hydroxide involved as our reactant, so it should be our second reactant in the second bimolecular step.

Thirdly, the product formed would be a combination of the anion and cation, one of our products, this means we have the following second step:

$(CH_3)_3С^+ (aq) + OH^- (aq)\rightarrow (CH_3)_3COH (aq)$

Another way is to verify this knowing that by adding all of the steps should yield a net equation, notice if we add the two steps together (reactants on one side and products on the other), we obtain:

$(CH_3)_3С^+ (aq) + OH^- (aq) + (CH_3)_3CBr (aq)\rightarrow (CH_3)_3COH (aq) + (CH_3)_3C^+ (aq) + Br^- (aq)$

Notice that the intermediate carbocation cancels out on both sides to yield the final net equation:

$OH^- (aq) + (CH_3)_3CBr (aq)\rightarrow (CH_3)_3COH (aq) + Br^- (aq)$

This means we have the correct second step.