Complete the sentences about the kinetic molecular model of gases:

(i) Gas molecules travel at high speeds in constant, ............................................................ directions. (ii) Except during collisions, the forces between the molecules of an ideal gas are ............................................................ . (iii) A gas exerts a pressure on the container walls because the moving molecules ............................................................ with the walls. (iv) If the temperature of a gas in a constant volume container increases, the speed of its molecules increases, which causes the pressure to ............................................................ .

The Kelvin (absolute) temperature scale is defined relative to absolute zero.

(i) State the temperature of absolute zero in degrees Celsius (${}^{\circ }C$).

Lowest possible temperature = .................................... ${}^{\circ }C$ (ii) State the value of the freezing point of water ($0{}^{\circ }C$) in kelvin ($K$).

Freezing point of water = .................................... $K$