Question

The characteristics of the blue solution formed from adding sodium to liquid ammonia is/are:

• A. The solution is diamagnetic
• B. The solution is paramagnetic
• C. The solution can reduce benzene rings
• D. The solution can conduct electricity

Answer 1

Answer: (B), (C), (D)

The correct options are
B The solution is paramagnetic
C The solution can reduce benzene rings
D The solution can conduct electricity

When alkali metals are dissolved in $liq.N{H}_3$ they release electrons. For example, when sodium metal is dissolved in $liq.N{H}_3$, the solution becomes blue due to the release of electrons.

$Na\left(s\right)+(x+y)N{H}_3\left(l\right)\to Na\left(N{H}_3{)}_x^{+}\right(l)+\underset{\text{blue}}{e^{-}\left(N{H}_3{)}_y\right(l)}$

Because of the free electrons, the solution is paramagnetic in nature and it also conducts electricity.

Electrons are highly reducing in nature. In reactions, $Nainliq.N{H}_3$ is used for the reduction of benzene rings and is commonly known as Birch reduction.