Table salt becomes sticky in the presence of moisture because :

1. It is deliquescent
2. It is hygroscopic
3. It contains impurities which are deliquescent
4. It is a good drying agent.

Which of the following substances can act as a dehydrating as well as a drying agent.

1. Oxalic acid
2. Conc. nitric acid
3. Washing soda
4. Conc sulphuric acid

If a salt on heating gives water vapour, then that salt is:

1. Hygroscopic
2. Deliquescent
3. Hydrated
4. Anhydrous

The salt which is the cause of hardness in water:

1. Sodium sulphate
2. Magnesium bicarbonate
3. Sodium chloride
4. Calcium nitrate