Which reaction of ammonia does not involve the non-bonding pair of electrons on the nitrogen atom?

A NH3(g) + CH3I(g) → CH3NH 3+ I –(s)
B NH3(g) + HCl (g) → NH4Cl (s)
C 2NH3(l) + 2Na(s) → 2NaNH2(s) + H2(g)
D 2NH3(aq) + Ag+(aq) → [Ag(NH3)2]+(aq)

Answer: C
And explanation please! Thanks!

2 answers

:NH3 + Na.
Here is the best I can do for Lewis structure of NH3.
H
..
:N:H + Na.
..
H
Let's pick on the right most H. It leaves and takes its electron with it as H.
The Na. donates its electron to make ionic bond and one molecule of NaNH2 with Na^+ charge and NH2^- with H. left over. Take another Na. and another NH3 and do the same thing. That gives you two molecules of NaNH2 (ionic compound) and two H. atoms and they combine to form H:H We never touched the non-bonding pair.
In A answer the H^+ sits down on the non-bonding pair to make the + ion (it's now bonding isn't it).
In B the H from HCl does the same think to form the NH4^+.
In C the explanation is above and the non-bonding is not used.
In D the non-bonding pair of those NH3 molecules goes to fill up the unused orbitals in Ag^+. Remember that a Lewis base is one that donates electrons; the NH3 donates electrons to the Ag^+
Well, it's still too confusing. Make it simple.
Thankyou smart human.