Question

A window of a car is found to be covered with 0.9cm of ice. If the area of the window is 1 m2, and the ice is at -12 degrees Celsius, what is the minimum heat required to melt all the ice? Take the density of ice to be 900 kg/m3, the specific heat capacity of ice to be 0.5 cal/g*K, and the latent heat of fusion to be 80 cal/g. Answer in kcal.

Answer 1

density = mass/volume

volume of the ice on the car window = height*area = 0.009m*1 = 9.0*10^-3

mass = 900*9.0*10^-3 = 8.1 kg

q = m*S*DT

q = 8100*0.5*(0+12)

q = 48600

heat of fusion = mass* latent heat = 8100*80 = 648000 cal

heat required to supply is = q +latent heat of fusion

                                     = 48600 + 648000

                                     = 696600 cal

                                     = 696.6 K cal