How many calories are released when 500 g of water cools from 95.0°C to 25.0°C?

35,000 cal will released.

Explanation:

By definition 1 kcal (=1000 calorie) is the approximate amount of energy released when the temperature of 1.000 kg of water is lowered by 1.000 °C (at a pressure of one atm.). It is about 4.2 kJ of energy.

q = mC∆T

where q = heat (calories); m = mass (500g); C = specific heat (1 cal/g/deg); ∆T = change in temp. Thus,

q = (500 g) (1 cal/g/deg) (95-25) = (500) (1) (70) = 35,000 cal