Question

Sodium forms a crystalline ionic solid with dihydrogen. The solid is nonvolatile and non-conducting in nature. It reacts violently with water to produce dihydrogen gas. Write the formula of this compound and its reaction with water. What will happen on electrolysis of the melt of this solid.

Answer 1

Sodium reacts with Dihydrogen to form sodium hydride which is a crystalline ionic solid.

\[\ce{2Na + H2 -> 2Na + H-}\]

It reacts with \[\ce{H2O}\] to produce \[\ce{H2}\] gas

\[\ce{2NaH + 2H2O -> 2NaOH + 2H2}\]

Although \[\ce{Na+H-}\] does not conduct electricity in the solid-state, the electrolysis of its melt produces \[\ce{H2}\] at the anode and Na at the cathode.

At cathode At anode

\[\ce{Na+H- ->[Electrolysis] 2Na (l) + H2 (g)}\]

Their melts conduct electricity and on electrolysis liberate Dihydrogen gas at anode, which confirms the existence of H-ion.

The Physical Properties of Hydrogen are-

• Hydrogen is a gas with no color and no odor 

• Hydrogen has the least density of all gases. 

• Hydrogen is viewed as the clean fuel of the future which is developed from water and returned back to water when oxidized.

• Hydrogen is present in almost all molecules in living things. 

• It remains connected with carbon and oxygen atoms. 

• Hydrogen is the most plentiful element in the whole universe. It is present as a gas in the atmosphere in 1 part per million volume. 

• It is spotless, non-toxic, and safe to produce from various sources.

• It is named an energy carrier because it stores energy that is first created somewhere else.