Question

How much water at 10°C can be heated to 40°C by the heat evolved from cooling 300g of water from 80°C to 40°C?

Answer 1

[mass cool H2O x specific heat H2O x (Tfinal-Tinitial)] + [mass warm H2O x specific heat H2O x (Tfinal-Tinitial)] = 0

mass cool H2O = x
look up specific heat H2O
Tf cool H2O = 40
Ti cool H2O = 10
mass warm H2O = 300 g
Tfinal warm water = 40
Tinitial warm water = 80
Solve for x