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View Full Version : Specific Latent Heat of Fusion problem


9giddjl
Nov19-08, 06:34 AM
1. The problem statement, all variables and given/known data

An ice tray containing 200 g of water at 25 degrees celecius is placed in the freezer. How much heat energy has to be removed to change the water into ice at -4 degrees celcius?

2. Relevant equations

Q= mc(Tf-Ti) + MLf + mc(Tf-Ti)

3. The attempt at a solution
I know that the water is changing into ice however im stumped because I don't know if the water is turning to -4 degrees celcius or 0 degrees celcius?

Any help will be muchly appreciated
Thankyou

Welshy
Nov19-08, 08:44 AM
Break it into 3 stages.

The water drops to freezing point. Then it freezes into ice. Then it drops to -4 degrees.

9giddjl
Nov20-08, 04:29 AM
i get it now!! Thankyou soo much!
Kind regards:)