What Went Wrong in Calculating Equilibrium Temperature?

AI Thread Summary
The discussion revolves around calculating the equilibrium temperature of a lead ball and water in a calorimeter. The user initially misapplied the specific heat capacities, using the specific heat of water for lead and vice versa. The correct specific heat for lead is not 0.13 J/g°C, which is actually the specific heat of water. After correcting the specific heat values and removing an unnecessary negative sign, the user successfully determined the equilibrium temperature. The importance of using accurate specific heat values in thermal calculations is emphasized.
mikep
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A 199 g lead ball at a temperature of 80.9°C is placed in a light calorimeter containing 178 g of water at 24.5°C. Find the equilibrium temperature of the system.

i used the equation Q = mc \Delta T
-(199g)(4.186J/g°C)(T - 80.9°C) + (178g)(0.13J/g°C)(T - 24.5°C) = 0
T = T final = 82.5°C
can someone please tell mw what i did wrong?
can someone also confirm if the specific heat for lead is 0.13J/g°C?
 
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mikep said:
can someone please tell mw what i did wrong?

You put the specific heat of water in the term for the lead ball, and vice versa.

can someone also confirm if the specific heat for lead is 0.13J/g°C?

Not off the top of my head, but if you type "specific heat lead" into Google, I'm sure you can find it.
 
oh yeah and i also didn't need the negative sign. i got it thanks
 

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