Given, mass of copper block m=5kg
Change in temperature (Δt)=500∘C
Specific heat s=0.39J(g−∘C)−1
Latent heat of fusion of water L=335Jg−1
Heat energy absorbed by copper block, Q1=msΔt
Let m′ kgof ice be melted.
Heat energy required to melt ice, Q2=m′L
But heat energy absorbed by copper block is heat energy utilised by ice in melting,Q1=Q2.
msΔt=m′L
or m′=LmsΔt =3355×0.39×500=2.9kg