Question

Which of the following is/are correct:-

• A. Deliquescent:- Sodium chloride Efflorescent:- Phosphorous pentaoxide
• B. Deliquescent:- Magnesium chloride Hygroscopic:- Silica gel
• C. Efflorescent:- Glauber's salt Hygroscopic:- Silica gel
• D. Efflorescent:- Quicklime Hygroscopic:- Caustic Soda

Answer 1

Answer: (B), (C)

The correct options are
B

Deliquescent:- Magnesium chloride

Hygroscopic:- Silica gel

C

Efflorescent:- Glauber's salt

Hygroscopic:- Silica gel

Efflorescent substances are those which lose water of crystallization when they are exposed to air.

Examples:- Washing soda $N{a}_{2}C{O}_3.10H_{2}O$, Glauber's salt $N{a}_{2}S{O}_4.10H_{2}O$ etc.

Deliquescent substances are those which absorb water when exposed to the atmosphere and form solutions.

Example:- Magnesium chloride $MgC{l}_2$, Calcium chloride $CaC{l}_2$, Caustic soda $NaOH$ etc.

Hygroscopic substances are those which absorb moisture from the atmosphere but not enough to form solutions.

Example:- Silica gel, Phosphorous pentaoxide, Quicklime etc.