A definite quantity of water and coconut oil are heated in separate test tubes using the same amount of heat.
Write any one practical application of this property.

$100 \mathrm{ml}$ each of coconut oil and water is taken in two beakers and kept in the freezer.

What difference can be observed in their volumes during freezing?

$100 \mathrm{ml}$ each of coconut oil and water is taken in two beakers and kept in the freezer.

What do you infer from the observation?

$100 \mathrm{ml}$ each of coconut oil and water is taken in two beakers and kept in the freezer.

When water is frozen in glass bottles, it is advised not to fill the bottles completely. Explain the reason.

What is surface tension?

Soap decreases the surface tension of water.

How does the decrease in surface tension benefit washing of clothes?

Some substances when, dissolved in water cause, the hardness of the water.

Which of the following substances, cause hardness of water? 

Sodium chloride, calcium bicarbonate, calcium carbonate, calcium sulphate, magnesium sulphate, calcium chloride, magnesium carbonate.