posted by olive on .
How long would it take a 1 200 W heater to melt 1.00 kg of ice at -12.0°C, assuming all the energy from the heater is absorbed by the ice? (Assume the specific heat of the ice is 2 090 J/kg · °C and the latent heat of fusion of water is 3.33 105 J/kg.)
what formula do you use, the fact it asks for time, throws me off
Calculate the number of Joules of heat required (Q), using the mass, specific heat of ice, temperature rise and latent heat of fusion.
Q = M[10 C(ice) + Latent heat]
= 1.00[10*2090 + 3.33*10^5]
= 3.54*10^5 J
Then divide that by the heating rate in Watts (J/s) for the answer in seconds.