# Thread: Thermodynamics Physics Problem: hot copper object placed in copper calorimeter

1. ## Thermodynamics Physics Problem: hot copper object placed in copper calorimeter

A 106-g piece of copper is heated in a furnace to a temperature tC. The copper is then inserted into a 150-g copper calorimeter containing 202 g of water. The initial temperature of the water and calorimeter is 16°C, and the final temperature after equilibrium is established is 38° C. When the calorimeter and its contents are weighed, 1.2 g of water are found to have evaporated. What was the temperature tC?

I tried to visualize this: so what happens is the hot piece of copper adds energy to the water, increasing the waters temperature up to 100 C and then the system loses mass because some of the water becomes vapor, finally the water cools down to 38 C. I'm super confused as to how to set this problem up.

2. ## Re: Thermodynamics Physics Problem: hot copper object placed in copper calorimeter

Set up a heat balance equation

Heat in = heat out
let tc = degrees above a reference temp of 16 C
106g copper *Cp copper* tc= 202 g water*(38-16)*Cpwater + latent heat of water at 27C(1,2g) (Water evaporates below its normal BP when the humidity of air above it is less than saturation at the water temp)

3. ## Re: Thermodynamics Physics Problem: hot copper object placed in copper calorimeter

I'm not sure what you mean by "let tc = degrees above a reference temp of 16 C" and your equation doesnt take into account that the calorimeter changes in temperature as well

4. ## Re: Thermodynamics Physics Problem: hot copper object placed in copper calorimeter

You supplied no info on calorimeter.If you know its weight and Cp you can correct for this.Without spec the copper might have been -150degrees C before heating.