Question

An open container holds ice of mass 0.500kg at a temperature of -16.1?C . The mass of the container can be ignored. Heat is supplied to the container at the constant rate of 850J/minute .

The specific heat of ice to is 2100 J/kg?K and the heat of fusion for ice is 334

Answer 1

Answer: Tmelt = 19.89mins

Explanation: (complete question- 334×10^3j/kg. How much time, Tmelt passes before the ice starts to melt?)

For ice to melt, its temperature must be 0* C.

Let

Q1 = heat required to raise the ice temp from -16.1 °C. to 0* C.

Q2 = heat required to melt the ice

Q1 = MCp(delta T)

Q2 = m(Hf)

where

M = mass of the ice = 0.500 kg (given)

Cp = specific heat of ice = 2100 J/kg K (given)

delta T = temperature change = 0 - -16.1= 16.1 °C. 

Hf = heat of fusion of ice = 334 x 10^3 J/jg.

Substituting values,

Q1 = 0.500× 2100× 16.1 = 16905J

Q2 = 0.500 × 334×10^3 = 167,000J

Heat required to melt the ice = Q1 + Q2 = 16905 + 167000 = 183905 J

How much time Tmelts = Q1/ 850 = 16905/850 = 19.89mins.