# Heat Transfer Equation

1. Dec 13, 2006

### chrispsu

im reviewing for my final in a few days an although this is a basic question i cant work out the correct answer for some reason. and i know i started the other thread below this one but i figured this was a different topic so the heading should be different lol

1. The problem statement, all variables and given/known data

A heat transfer of 8.8 x 10^5 J is required to convert a block of ice at -13°C to water at 13°C. What was the mass of the block of ice?

2. Relevant equations

Q=mc(ice)(tf-ti) + mLf + mc(water)(tf-ti)

3. The attempt at a solution

i tried: 8.8x10^5= m(2220)(13) + m(333) + m(4190)(13)
i come out with the 10.52kg which is not correct.
can someone help pinpoint what i am doing something wrong? thanks!

2. Dec 13, 2006

### Gokul43201

Staff Emeritus
Check those numbers. One of them is wrong - it's in the wrong units.

You need to be very careful with your units!

3. Dec 13, 2006

### chrispsu

oh ok....the heat of fusion should be 333x10^3...solving it out then i would get 2.11 which is the correct answer. I need to be less careless with my units! lol thanks alot!! :D