A piece of ice (heat capacity =2100 ~J ~kg ⁻¹ ^ C ⁻¹ and latent heat =3.36 10^5 ~J ~kg ⁻¹ ) of mass m gram is at -5^ C at atmospheric pressure. It is given 420 ~J of heat so that the ice starts melting. Finally when the ice-water mixture is in equilibrium, it is found that 1 ~g of ice has melted. Assuming there is no other heat exchange in the process, the value of m is

Step-by-step solution

Language of question is slightly wrong. As heat capacity and specific heat are two different physical quantities. Unit J - kg ⁻¹ ^ C ⁻¹ . The heat capacity given in the question is really the specific heat. Now applying the heat exchange equation. array r 420= (m 10⁻³ )(2100)(5)+ (1 10⁻³ ) (3.36 10^5 ) array Solving this equation we get, m=8 ~g The correct answer is 8 .