Question

Which of the following statements is false
(A) $CaOC{{l}_{2}}$ gives $OH^-$,$Cl^-$ and $OCl^-$ in aqueous solution
(B) Allotropes of carbon include diamond and graphite.
(C) Bleaching action of $C{{l}_{2}}$in moist conditions is not permanent
(D) Calomel is $H{{g}_{2}}C{{l}_{2}}$

Answer 1

Hint: There are four statements in the question. We must determine which is false. For this, we have to check the correctness of each of the statements.

Complete Step by Step Answer:
(A) $CaOC{{l}_{2}}$ gives $OH^-$,$Cl^-$ and $OCl^-$ in aqueous solution.
$CaOC{{l}_{2}}$ is the formula for bleaching powder. It is also known as calcium oxychloride. $CaOC{{l}_{2}}$ in aqueous solution can be written as $Ca{{(OCl)}_{2}}.Ca{{(OH)}_{2}}.CaC{{l}_{2}}.2{{H}_{2}}O$which will give $OH^-$,$Cl^-$ and $OCl^-$ . The given statement above is true. As a result, it is incorrect.
(B) Allotropes of carbon include diamond and graphite.
Pure carbon has three allotropes – diamond, graphite, and fullerene. Graphite is a soft, black, and slippery solid and is mostly used in lubricants or pencils. Diamond is very hard and is a good thermal conductor. Diamond dust is used nowadays in beauty products like facials as it has the property to reduce wrinkles. It is highly expensive. However, the purest allotrope of carbon is fullerene. The given statement above is true. As a result, it is incorrect.
(C) Bleaching action of $C{{l}_{2}}$ in moist conditions is not permanent.
This statement is false as the bleaching action of $C{{l}_{2}}$in moist conditions is permanent.


Coloured matter in the presence of nascent oxygen gives colourless matter.
(D) Calomel is $H{{g}_{2}}C{{l}_{2}}$
This statement is true. The calomel is mainly used as a saturated calomel electrode to measure potentials or pH in solutions.
Correct Option: (C) Bleaching action of $C{{l}_{2}}$in moist conditions is not permanent.

Note: All the other three options except (C) are true. Only the option (C) is false. Hence, it is the correct option.