Question

which uses correct mechanism arrows? a. chemical structure with h₃o⁺ and carboxylate ion, arrows + structure ⇌ h₂o and carboxylic acid b. similar with different arrows c. similar d. similar ○ a ○ b ○ c ○ d

Explanation:

To determine the correct mechanism arrows, we analyze the proton transfer and nucleophilic attack:

1. The hydronium ion ($\ce{H3O+}$) donates a proton. The arrow from $\ce{H}$ in $\ce{H3O+}$ to the $\ce{O}$ of the carboxylate (nucleophile) should show proton movement.
2. The carboxylate ($\ce{RCOO-}$) attacks a proton (from $\ce{H3O+}$), and the arrow for the lone pair on the carboxylate's $\ce{O}$ should point to the $\ce{H}$ being transferred.
3. In option C:

• The arrow from the $\ce{H}$ in $\ce{H3O+}$ (breaking the $\ce{O-H}$ bond) to the $\ce{O}$ of the carboxylate (forming a new $\ce{O-H}$ bond in the carboxylic acid) is correct.
• The arrow for the lone pair on the carboxylate's $\ce{O}$ (nucleophilic attack on $\ce{H}$) is also correctly directed.
• Other options have incorrect arrow directions (e.g., A/B/D misdirect arrows for proton transfer or nucleophilic attack).

Answer:

C