Embibe Experts Solutions for Chapter: Hydrogen, Exercise 4: EXERCISE-4

$100 \mathrm{kg}$ hard water contains $5 \mathrm{g} {\mathrm{MgSO}}_4$. Find hardness.

One litre hard water contains $1 \mathrm{mg} {\mathrm{CaCl}}_2$ and $1 \mathrm{mg} {\mathrm{MgSO}}_4$. Find hardness.

Calculate the hardness of water sample which contains $0.001 \mathrm{mol} {\mathrm{MgSO}}_4$ per litre of water.

(A) Draw the gas phase and solid phase structure of ${\mathrm{H}}_2{\mathrm{O}}_2$.
(B) ${\mathrm{H}}_2{\mathrm{O}}_2$ is a better oxidising agent than water. Explain.

Metal hydrides are ionic, covalent or molecular in nature. Among $\mathrm{LiH}, \mathrm{NaH}, \mathrm{KH}, \mathrm{RbH}, \mathrm{CsH}$, the correct order of increasing ionic character is:

Give reasons:
(A) Lakes freeze from top towards bottom.
(B) Ice floats on water.

Hydrogen generally forms covalent compounds. Give reason.

How will you account for $104.5^{°}$ bond angle in water?