The reaction $4{\mathrm{NH}}_3+5{\mathrm{O}}_2\to 4\mathrm{NO}+6{\mathrm{H}}_2\mathrm{O}$ is an example of

I. Combination        II. Displacement
III. Redox                IV. Neutralization

$\mathrm{I}.$ Iron is oxidised                            $\mathrm{II}.$ Water is reduced
$\mathrm{III}.$ Water acts as reducing agent   $\mathrm{IV}.$ Iron acts as reducing agent

Which of the following are exothermic reactions?

I. Dilution of an acid.

II. Reaction between water and quick lime.

III. Sublimation of camphor.

IV. Evaporation of a liquid.

Which of the following are endothermic reactions?

I. Dilution of an acid.        

II. Reaction between water and quick lime.

III. Sublimation of camphor. 

IV. Evaporation of a liquid.

The reaction between water and quick lime gives rise to calcium hydroxide. Which of the following statements are correct?

$\mathrm{I}.$ The reaction is exothermic

$\mathrm{II}.$ The pH of the final solution is less than $7$

$\mathrm{III}.$ The reaction is endothermic

$\mathrm{IV}.$ The pH of the final solution is greater than $7$