Name: Action of Sodium Hydroxide on Metallic Salt Solution
Uploaded: 2019-07-19
Duration: 5 min 16 s
Description: Sodium hydroxide (NaOH) is a base that reacts with aqueous solutions containing metallic ions. To know more about this reaction, let's see this video.

Question

A white amorphous powder is widely used in textile industry and as a disinfectant. What can it be? Give the principle of its preparation on a large scale. How does it react with the following substances?

(a) $HCl$

(b) ${COCl}_{2}$ solution

(c) Acidified aqueous solution of $KI$

Accepted Answer

The white amorphous powder, which is widely used in the textile industry and as a disinfectant is bleaching powder. Its chemical name is calcium hypochlorite $Ca (OCl) Cl$ or ${CaOCl}_{2}$ .

On a large scale, bleaching powder is prepared in the Hasenclever plant. The plant consists of cast-iron cylinders horizontally placed one above the other. Each of the cylinders is provided with a screw that keeps revolving slowly. Dry slaked lime is poured through a hopper at the top, and it passes through all the cylinders, one by one. A current of chlorine gas is led into the plant at the bottom. Slaked lime comes in contact with the current of chlorine gas travelling in the opposite direction. Bleaching powder is formed and falls into the casks below.

The chemical equation is:

$\underset{\underset{hydroxide}{Calcium}}{Ca (OH)_{2}} + \underset{Chlorine}{{Cl}_{2}} \to \underset{\underset{hypochlorite}{Calcium}}{Ca (OCl) Cl} + \underset{Water}{H_{2} O}$

(a) Bleaching powder reacts with dilute hydrochloric acid; chlorine is liberated.

The chemical equation is:

$\underset{\underset{hypochlorite}{calcium}}{Ca (OCl) Cl} + \underset{\underset{acid}{Hydrochloric}}{HCl} \to \underset{\underset{chloride}{Calcium}}{{CaCl}_{2}} + \underset{water}{H_{2} O} + \underset{Chlorine}{{Cl}_{2} ↑}$

(b) In the presence of, ${COCl}_{2}$ solution, bleaching powder loses its oxygen.
$2 \underset{\underset{hypochlorite}{Calcium}}{Ca (OCl) Cl} \overset{{COCl}_{2}}{\to} 2 \underset{\underset{chloride}{Calcium}}{{CaCl}_{2}} + \underset{Oxygen}{O_{2}} ↑$
In this reaction, ${COCl}_{2}$ acts as a catalyst.

It liberates iodine from an acidified aqueous solution of potassium iodide.

$\underset{\underset{hypochlorite}{Calcium}}{Ca (OCl) Cl} + \underset{\underset{Iodide}{Potassium}}{2 KI} + \underset{\underset{acid}{Hydrochloric}}{2 HCl} \to \underset{\underset{chloride}{Calcium}}{{CaCl}_{2}} + \underset{Water}{H_{2} O} + \underset{\underset{chloride}{Potassium}}{2 KCl} + \underset{Iodine}{I_{2}}$

A white amorphous powder is widely used in textile industry and as a disinfectant. What can it be? Give the principle of its preparation on a large scale. How does it react with the following substances?

(a) $HCl$

(b) ${COCl}_{2}$ solution

(c) Acidified aqueous solution of $KI$

Important Questions on Compounds of Common Use

Learn and Prepare for any exam you want !

A white amorphous powder is widely used in textile industry and as a disinfectant. What can it be? Give the principle of its preparation on a large scale. How does it react with the following substances? (a) HCl (b) COCl2 solution (c) Acidified aqueous solution of KI

Important Questions on Compounds of Common Use

Learn and Prepare for any exam you want !

A white amorphous powder is widely used in textile industry and as a disinfectant. What can it be? Give the principle of its preparation on a large scale. How does it react with the following substances?

(a) $HCl$

(b) ${COCl}_{2}$ solution

(c) Acidified aqueous solution of $KI$