The correct option is C 8 litres
Given:
Mass of the ice, mi=10 kg
Specific heat capacity of water, cw=4200 J kg−1 ∘C−1
Specific latent heat of melting of ice, Li=336×103 J kg−1
Temperature of water, tw=100∘C
Amount of heat energy required to melt the ice, Qi=mi×Li=10×336×103 J=336×104 J ---- (1)
Since the ice completely melts into water, the final temperature would be 0∘C.
Change in the temperature, Δt=100−0=100∘C
Let the mass of the water required be mw.
Heat energy supplied by the boiling water, Qw=mw×cw×Δt
Qw=mw×4200×100=mw×104 J ---- (2)
Assuming there is no heat loss in any other form, according to the principle of method of mixtures, Qi=Qw
⟹336×104=42×104×mw
⟹336=42×mw
⟹mw=33642=8 kg
Since, for water, 1 kg=1 litre, the amount of water needed would be 8 litres.