Chapter 3, Water (ICSE)

Efflorescence is the process in which

• • a) A substance absorbs moisture from the air

• • b)A substance loses water of crystallization to the atmosphere

• • c) A substance dissolves in its own absorbed moisture

• • d) A substance forms crystals on cooling

Which of the following is a hygroscopic substance?

• Sodium chloride
• Silica gel
• Copper sulfate pentahydrate
• Baking soda

Deliquescence refers to:

• The process of losing water of crystallization
• The absorption of moisture from the air to form a solution
• The process of forming crystals from a solution
• The removal of moisture from a substance

A solution in which no more solute can be dissolved at a given temperature is called:

• Unsaturated solution
• Dilute solution
• Saturated solution
• Supersaturated solution

Which of the following will show efflorescence?

• Calcium chloride (CaCl₂)
• Washing soda (Na₂CO₃·10H₂O)
• Sodium hydroxide (NaOH)
• Table salt (NaCl)

A substance that absorbs moisture from the air without dissolving in it is called:

• Hygroscopic
• Efflorescent
• Deliquescent
• Crystalline

Which of the following is an example of a deliquescent substance?

• Sodium chloride
• Potassium nitrate
• Sodium hydroxide
• Copper sulfate

A solution that contains less solute than it can dissolve at a given temperature is called:

• Saturated solution
• Supersaturated solution
• Unsaturated solution
• Concentrated solution

When a substance absorbs moisture and turns into a liquid, the process is called:

• Efflorescence
• Hygroscopy
• Deliquescence
• Crystallization

The process of forming crystals by removing water from a solution is called:

• Evaporation
• Crystallization
• Deliquescence
• Efflorescence