In the Brønsted–Lowry model, what is the conjugate base of $N_4^{+}$ (ammonium)?

• A. $N_2$
• B. $N_3+$
• C. $N_4$
• D. $N_3$

Answer: (D)

Verified step by step guidance

1. Recall that in the Brønsted–Lowry acid-base theory, an acid is a proton (H⁺) donor and a base is a proton acceptor.
2. Identify the species given: ammonium ion, \(\mathrm{NH_4^+}\), which can act as an acid by donating a proton.
3. Determine the conjugate base by removing one proton (H⁺) from the acid \(\mathrm{NH_4^+}\).
4. Removing one proton from \(\mathrm{NH_4^+}\) results in \(\mathrm{NH_3}\), which is the conjugate base.
5. Therefore, the conjugate base of \(\mathrm{NH_4^+}\) is \(\mathrm{NH_3}\).