## heat problem

How much heat (in kj) is given out when 85.0g of lead cools from 200 degrees celsius to 10 degrees celsius? (Cp of lead is 0.129 J/g-celsius

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### Re: heat problem

[quote="lilromo89"]How much heat (in kj) is given out when 85.0g of lead cools from 200 degrees celsius to 10 degrees celsius? (Cp of lead is 0.129 J/g-celsius[/quote]

What equation do you think you should use here?

Looking at the units of the heat capacity (C[sub]p[/sub]) that you have, it looks like the equation should be:

C[sub]p[/sub] =[u][color=#dddddd]E[/color] ∆H [color=#dddddd]C[/color][/u]
[color=#dddddd][sub]p[/sub] =AE[/color][sup]m×∆T[/sup]
Where ∆H is the Change in heat (in J)
m = mass of object (in g)
∆T = Change in Temperature (in °C or K)

Rearrange & calculate!
(Remembering at the end that 1000J == 1kJ)

2083.35kj

### Re: heat problem

[quote="allan_chemist"]Where ∆H is the Change in heat ([color=Red][b]in J[/b][/color])
m = mass of object (in g)
∆T = Change in Temperature (in °C or K)

Rearrange & calculate!
([color=Red][b]Remembering at the end that 1000J == 1kJ[/b][/color])[/quote]

[quote="lilromo89"]2083.35kj[/quote]

Yes, that's correct, but your units are in correct.
Note the bits I have highlighted in red, then adjust your units!

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