R.R. Mishra Solutions for Exercise 6: Multiple Choice Questions (MCQ)

Which one of the following gases is used to prevent rancidity while packing fatty foods?

 

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

For the reaction $3\mathrm{Fe}\left(\mathrm{s}\right)+4{\mathrm{H}}_2\mathrm{O}\left(\mathrm{g}\right)\to {\mathrm{Fe}}_2{\mathrm{O}}_3\left(\mathrm{s}\right)+4{\mathrm{H}}_2\left(\mathrm{g}\right)$ which of the following statements are correct?

$\mathrm{I}.$ 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.

In each of the beakers marked A, B and C, $25 \mathrm{mL}$ of water was taken. Small amounts of sodium hydroxide, anhydrous copper sulphate and ammonium chloride were added to beakers A, B and C respectively. An increase of temperature in beakers A and B were observed while there was a fall of temperature in beaker C. Which of the following statements are correct?
I. Changes in beakers A and B are endothermic.
II. Changes in beakers A and B are exothermic.
III. Change in beaker C is endothermic.
IV. Change in beaker C is exothermic.

When a solution of ferrous sulphate (${\mathrm{FeSO}}_4$) is added to an acidified purple solution of potassium permanganate (${\mathrm{KMnO}}_4$), the purple colour fades and finally disappears. Which one of the following statements is correct?

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 $7$