Determine the ammonium ion formed in the following reaction between diethylamine and hydrobromic acid.

• A.
• B.
• C.
• D.

Answer: (D)

Verified step by step guidance

1. Identify the reactants: diethylamine (a secondary amine) and hydrobromic acid (HBr). Diethylamine has the structure where a nitrogen atom is bonded to two ethyl groups (CH3CH2-) and one hydrogen.
2. Understand the reaction type: Amines are basic and can accept a proton (H+) from acids like HBr. When diethylamine reacts with HBr, the nitrogen atom will accept a proton, forming an ammonium ion.
3. Determine the charge on nitrogen after protonation: The nitrogen in diethylamine has a lone pair that accepts a proton, resulting in a positively charged ammonium ion (N+).
4. Draw the ammonium ion: The nitrogen will be bonded to two ethyl groups, one hydrogen from the original amine, and one additional hydrogen from the protonation, giving it four bonds and a positive charge.
5. Match the correct structure: The ammonium ion formed will have the nitrogen with a positive charge, bonded to two ethyl groups and two hydrogens. This corresponds to the structure where nitrogen is positively charged and bonded to H, CH2CH3, and another CH2CH3 group.