[soolee]

I have this specific heat problem and I think I got the answer right but it( sciencegeek.net)'s telling me that I got it wrong.
It doesn't tell me the right answer

here it is

How much energy must be removed from 500grams of water in order to cool it from 80°C to 40°C? The specific heat of water can be found on your periodic table

and I did (500g)(40°)(4.184) and got 83680 what did I do wrong??

[mjc123]

That looks right to me, I don't know why they say it's wrong.
Have you used the same number of significant figures as the value they give you for Cp?

[DrCMS]

What are the units?

[soolee]

well the capacity was 4.184 J

so should I put 8.368 X 10^5??

[mjc123]

No, because it's 8.368 x 10^4 J
You got the answer right. I don't know what the website's gripe is. Move on.

[DrCMS]

I agree the answer is 83680J but the website may be wanting 83.68 kJ or a variation with less significant figures given the accuracy of the weight and temp change etc.