Boiling of a liquid takes place at

State whether the following statement is true or false:
The term $vapor$ describes the gaseous state of a substance that normally exists as a liquid or solid.

How does the melting point of a substance indicate the strength of its intermolecular forces of attraction?

$(a)$ What temperature in Kelvin scale is equal to $50^{\circ} C$?
$(b)$ Describe an activity to show that the rate of evaporation increases with surface area.

Carbon dioxide was taken in an enclosed cylinder and compressed by applying pressure.
$(a)$ Which state of matter will we obtain after completion of the process?
$(b)$ Name and define this process.
$(c)$ What is the common name of the product obtained in the above process?

$(i)$ Write the full form of $(a)$ $LPG$ $(b)$ $CNG$.
$(ii)$ Give one use of each.