The specific latent heat of vapourization of lead is 8.7 × \(10^5 Jkg_1\). This means that 8.7 × \(10^5\) J of thermal energy is required to change

A.

a given mass of molten lead to vapour at constant temperature and pressure.

B.

1 kg of molten lead to vapour at constant temperature and pressure.

C.

1 kg of solid lead to vapour at constant temperature and pressure.

D.

1 kg of molten lead to vapour for every degree rise in temperature.

Correct answer is B

The specific latent heat of vaporization of lead is the amount of thermal energy required to change 1 kg of molten lead to vapor at constant temperature and pressure.