3. Acids and Bases

Each of these compounds can react as an electrophile. In each case, use curved arrows to show how the electrophile would react with the strong nucleophile sodium ethoxide, Na^{+ −}OCH₂CH₃.

(c) CH₃CH₂Br

(d) BH₃

In each reaction, label the reactants as Lewis acids (electrophiles) or Lewis bases (nucleophiles). Use curved arrows to show the movement of electron pairs in the reactions. Draw any nonbonding electrons to show how they participate in the reactions.

(b)

In each reaction, label the reactants as Lewis acids (electrophiles) or Lewis bases (nucleophiles). Use curved arrows to show the movement of electron pairs in the reactions. Draw any nonbonding electrons to show how they participate in the reactions.

(a)

Each of these compounds can react as a nucleophile. In each case, use curved arrows to show how the nucleophile would react with the strong electrophile BF₃.

(a)

(b)

Which of the following analogies best describes the induced-fit model of enzyme-substrate binding?

Which graph best represents the energy profile of a reaction when an enzyme is present?

In the context of reaction mechanisms, what do both the $\rho$-dependent and $\rho$-independent mechanisms of termination have in common?