Solveeit Logo

Question

Question: Highly pure dilute solution of sodium in liquid ammonia_______ A. Shows blue colour B. Exhibit...

Highly pure dilute solution of sodium in liquid ammonia_______
A. Shows blue colour
B. Exhibit electric conductivity
C. Produces sodium amide
D. Produces hydrogen gas

Explanation

Solution

Hint: Sodium is a metal and ammonia are a base when a base reacts with a metal, salt and gas(hydrogen) are produced with a popping sound.

Complete answer:
When sodium is dissolved in liquid ammonia, the electrons are produced in solution. These electrons produce a deep blue colour. But if the solution is made concentrated or the concentration of solution is increased, the colour of solution changes to be bronze or like that of copper.
The solution of metal Sodium and base Ammonia produces cations and anions. The electric current is carried by electrons. Hence, the solution exhibits electric conductivity due to the presence of electrons and ions (cations and anions).
The solvated electron is highly responsible for both the conduction of electricity and the colour production. The solvated ion is highly stable and is formed when electrons are surrounded by Ammonia molecules in solution.
The solution of liquid Ammonia and sodium is very stable so further reaction, if any, occurs only when a catalyst is added or present. So, the formation of sodium iodide is not natural or spontaneous without a catalyst and does not occur generally. Same is with the production of hydrogen gas. Hydrogen gas is produced as a by-product if sodium iodide is formed.

The correct answer is (A) and (B).

Note: Ferric chloride is used as a catalyst for the reaction which produces sodium iodide and hydrogen gas. Ferric chloride in a balanced equation produces two moles of sodium iodide and one mole of hydrogen gas from two moles of sodium and Ammonia each.