The correct option is A 0∘C
Given that,
Latent heat of fusion of ice (Lf)=80 cal/g
Specific heat capacity of water (cw)=1 cal/g∘C
Mass of ice (mi)=100 g
Mass of water (mw)=100 g
Initial temperature of ice (T1)=0∘C
Initial temperature of water (T2)=80∘C
Let the temperature of mixture be T.
Heat required to melt 100 g of ice to water is Q1=miLf=100×80=8000 cal
& Heat required to reduce the temperature of water from 80∘C to 0∘C is
Q2=mwcwΔT=100×1×(80−0)=8000 cal
∵Q1=Q2
From the priciple of calorimetry, we can say that heat released from the cooling of water at 80 ∘C will used to just melt the given mass of ice. At equilibrium, temperature of the system will be 0∘C.
Thus, option (a) is the correct answer.