Metals like platinum and palladium can absorb large volumes of hydrogen under special conditions. Such adsorbed hydrogen by the metal is known as

$NaH$ is an example of:

Lithium aluminium hydride reacts with silicon tetrachloride to form:

On reaction with $Mg$,very dilute nitric acid produces

Assertion : Sulphuric acid is more viscous than water.
Reason : Concentrated sulphuric acid has a great affinity for water.

Complete the following reactions:
$(i)$ $H_{2(g)} + M_mO_{o(s)} \xrightarrow{\Delta} M_{(s)} + H_2O_{(l)}$
$(ii)$ $CO_{(g)} + 2H_{2(g)} \xrightarrow{\Delta, \text{ catalyst}} CH_3OH_{(l)}$
$(iii)$ $C_3H_{8(g)} + 3H_2O_{(g)} \xrightarrow{\Delta, \text{ catalyst}} 3CO_{(g)} + 7H_{2(g)}$
$(iv)$ $Zn_{(s)} + 2NaOH_{(aq)} \xrightarrow{\text{heat}} Na_2ZnO_{2(aq)} + H_{2(g)}$