$(a)$ Define boiling point.
$(b)$ Express the boiling point of water in Celsius as well as Kelvin scale.
$(c)$ $A$ diver is able to cut through water in a swimming pool. Which property of matter does this observation show?

State whether the following statement is true or false:
$-273^{\circ} C = 0 K$

Explain the following:
$(i)$ Gases exert pressure on the walls of the container.
$(ii)$ Water is liquid at room temperature.
$(iii)$ Evaporation causes cooling.

Why do gases show high compressibility?

Explain:
$(a)$ Sponge,though compressible,is a solid.
$(b)$ Gases completely fill the vessel in which they are kept.

Fill in the blanks :
$(a)$ Evaporation of a liquid at room temperature leads to a ........... effect.
$(b)$ At room temperature,the forces of attraction between the particles of solid substances are ........... than those which exist in the gaseous state.
$(c)$ The arrangement of particles is less ordered in the ........... state. However,there is no order in the ........... state.
$(d)$ ........... is the change of solid state directly to vapour state without going through the ........... state.
$(e)$ The phenomenon of change of a liquid into the gaseous state at any temperature below its boiling point is called ...........