Question

When a mixture of common salt and ammonium chloride is heated it is observed that

• A. solid common salt get deposited on the cooler part of the funnel while solid Ammonium Chloride remain in the China dish
• B. the mixture of common salt and ammonium chloride turns into greased crystal when allowed to cool
• C. The ammonium chloride gets deposited on the cooler part of the funnel and solid common salt remain in the China dish
• D. The droplet containing both common salt and ammonium chloride appears on the upper part of the funnel while some molten mixture of common salt and ammonium chloride remains in the China dish.

Answer 1

The correct option is C

The ammonium chloride gets deposited on the cooler part of the funnel and solid common salt remain in the China dish

Separation of a mixture of common salt and ammonium chloride:

This method is used in the separation of such solid-solid mixtures where one of the components sublimes on heating.

However, it is useful only if the components of the mixture do not react chemically on heating.

Method:

1. Place the mixture of common salt and ammonium chloride in a china dish and heat it over a low Bunsen flame.
2. Place a clean glass funnel in an inverted position in the china dish and close the mouth of its stem with cotton wool.
3. The ammonium chloride in the mixture sublimes to form dense white fumes. These fumes condense on the cooler sides of the funnel in the form of fine white powder.
4. When the mixture gives off no more white fumes, lift the funnel, and scrap the fine white powder from its sides on a piece of paper. This is pure ammonium chloride. The residue left behind in the funnel is sodium chloride.

When a mixture of common salt and ammonium chloride is heated it is observed that ammonium chloride gets deposited on the cooler part of the funnel and solid common salt remains in the China dish.

Hence, Option(C) is correct.