7. Calculate the amount of energy required heat 100.g to
H2O(s) changes to H2O(l) at 0°C

33300J

Explanation:

Given parameters:

Mass of ice  = 100g

Unknown:

Amount of energy = ?

Solution:

This is a phase change process from solid to liquid. In this case, the latent heat of melting of ice is 3.33 x 10⁵ J/kg.

 So;

            H  = mL

m is the mass

L is the latent heat of melting ice

  Now, insert the parameters and solve;

            H = mL

 mass from gram to kilogram;

            100g gives 0.1kg

  H = 0.1 x 3.33 x 10⁵ = 33300J