Question

IP A 1.4-kg block of ice is initially at a temperature of -5.0 ∘C.

Part A

If 2.5×10⁵ J of heat are added to the ice, what is the final temperature of the system?

Part B

Find the amount of ice, if any, that remains.

Answer 1

Mass m = 1.4 kg

Initila tmepearture t = -5 ^o C

Heat added Q = 2.5 x10 ⁵ J

Specific heat of ice C = 2060 J / kg ^o C

Amount of heat required to raise the temperature of ice from -5 ^o C to 0 ^o C is Q ' = mC(0-(-5))

   Q ' = 1.4x2060x5

        = 14420 J

Remaining heat Q " = Q - Q '

                            = 235580 J

Latent heat of fusion of ice L = 333.55x10 ³ J/ kg

Amount of ice melted due to Q " heat is M = Q " / L

            M = (235580) /(333.55x10 3)

                = 0.7062 kg

Final temperature of the system = 0 ^o C

(B). Amount ice remained = m - M

                                       = 1.4 - 0.7062

                                       = 0.6937 kg