(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A 0.2 kg block of ice at -15*C is placed into a pan on a stove, heated to a liquid, and then to vapour with a final temperature of 115*C. Calculate the total amount of heat required for this process.

2. Relevant equations

Eh = mc(t2 - t1)

Lf (or Lv) = Eh / m

3. The attempt at a solution

Etotal = Emelting + Evapourization

Emelting = mct

= (0.2kg)(4.2x10^3)(0+15*C)

= 12 600 J

Evapourization = mct

= (0.2kg)(4.2x10^3)(115-0*C)

= 96 600 J

Etotal = 12600 + 96 600J

= 109 200 J or 1.1 x 10^5

What am i doing wrong? The answer is 6.2 x 10^5 J.

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# Homework Help: Changes of state and latent heat

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