Question

Which of the following process/processes release heat ?

1. condensation
2. vaporisation
3. freezing
4. melting

Options

• only (i)

• only (iv)

• (i) and (iii)

• (ii) and (iv)

Answer 1

(i) and (iii)

Both condensation and freezing release heat that lead to decrease in kinetic energy of molecules. When the substance gets cool enough its particles become slower or stop their movement and change their phase into liquid and solid on condensing and freezing respectively.