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Dx
May13-03, 04:49 PM
Hello,

150kcal of heat raises the temp of 2.0kg of material by 400 degrees F. Whats the materials specific heat capacity?

I cam up with 1.35 kcal/kg degrees C. is this correct?

Thanks!
Dx [;)]

Tom Mattson
May13-03, 05:00 PM
Dx,

That's not what I get. Can you show me what you did?

Thanks,

Dx
May13-03, 05:16 PM
Originally posted by Tom
Dx,

That's not what I get. Can you show me what you did?

Thanks,

No problem, Tom! I meant to say .34 kcal/fg oC was my answer sorry thats another problem i am working on but i got it wrong anyways, lol.

I used the formula [del]Q = mc [del]T and substituted.
c = 150kcal / (2kg)* (190oC) =
.34 kcal

i figured it was .34 since when i converted from F to C i rounded the number so then I usd scientific notation to conclude to this answer.
I am sorry but I have reworked this problem many times erasing and adding to it so excuse me if its not exact but you can see I am really trying here.
Thanks!
Dx

Tom Mattson
May13-03, 05:34 PM
OK, that's what I got too.

I was thinking you had made a mistake converting ΔTF to ΔTC (because you have to multiply by 5/9), but then I reworked the problem by making that mistake, and I still did not get your answer.

Oh well, that's cleared up now.

Dx
May13-03, 05:39 PM
Just wanted to say thanks!