15 Rate of loss of mass = 2.25 g per minute
= 0.002 25
60 = 3.75 × 10–5 kg s–1
Rate of supply of energy to alcohol = 40 × 80%
= 32 W
So specific latent heat of vaporisation
= rate of supply of energy
rate of loss of mass = 32
3.75 × 10–5
= 853 000 J kg–1 ≈ 850 kJ kg–1
its in new book