Question

Hydrolith, a source of hydrogen is:
(A) NaH
(B) $\text{Ca}{{\text{H}}_{\text{2}}}$
(C) LiH
(D) $\text{Ba}{{\text{H}}_{\text{2}}}$

Answer 1

Before we know the formula of Hydrolith, we should be knowing about the compound. Hydrolith is a binary compound, which is salt like in nature. It is also a source of hydrogen.

Step by step answer: Hydrolith is formed when calcium metal is heated with hydrogen. Hydrolith is also considered to be a strong reducing agent. Therefore, the correct answer to Hydrolith is $\text{Ca}{{\text{H}}_{\text{2}}}$.
Hydrolith is an alkaline earth hydride. The color of Hydrolith is usually grey, but when pure it is white. The reaction for the formation of Hydrolith is considered as one of the main sources of production of hydrogen.
When Hydrolith reacts with water, it releases dihydrogen gas. The difference in using Hydrolith other than hydrogen is that when it reacts with ordinary water, it is comparatively slower. But the bond formation of Hydrolith is comparatively stronger with other elements, as compared to hydrogen.
The reaction between calcium and hydrogen to form the compound Hydrolith is given below:
$\text{Ca+}{{\text{H}}_{\text{2}}}\xrightarrow{\text{300 }\\!\\!{}^\circ\\!\\!\text{ C - 400 }\\!\\!{}^\circ\\!\\!\text{ C}}\text{ Ca}{{\text{H}}_{\text{2}}}$
The reaction mentioned above takes place at a temperature of about $\text{300 }\\!\\!{}^\circ\\!\\!\text{ C - 400 }\\!\\!{}^\circ\\!\\!\text{ C}$.
Calcium Hydrolith is a relatively mild desiccant and, compared to molecular sieves, probably inefficient. Hydrolith is much safer than most of the reactive agents such as sodium metal or sodium – potassium alloy.

Note: There are various drawbacks in case of Hydrolith. Some of them are as follows:

• Hydrolith is insoluble in all solvents with which it does not react vigorously. So the speed of the drying action of Hydrolith is slow.
• Because Hydrolith and calcium hydroxide are similar in appearance, the quality of a sample of Hydrolith is not obvious visually.