What is the Total Heat Capacity of the Calorimeter?

AI Thread Summary
The discussion revolves around calculating the total heat capacity of a calorimeter after mixing two water samples at different temperatures. The initial calculations incorrectly summed the heat exchanges, leading to confusion about the correct method. It is clarified that the heat lost by the hot water must equal the heat gained by the cold water and the calorimeter, requiring a proper application of the heat transfer equation. Participants emphasize the importance of correctly accounting for heat loss and gain, suggesting a need for detailed work to identify errors. Ultimately, the correct total heat capacity should align with the expected value of 493.24 J/K.
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Homework Statement



50ml of water at 49.6 C were mixed with 50ml of water at 25.1 C in a calorimeter also at 25.1 C. The final temperature was 30.1 C Assuming that neither the density of water nor its specific heat capacity change with temperature, calculate the total heat capacity of the calorimeter.


Homework Equations



Density of water = 1.00 g/mL
Specific heat capacity = 4.18 J / g * K

The Attempt at a Solution



q (heat given up by water) = 50ml * (49.6-30.1)
= 840 cal

q (heat absorbed by cold water) = 50ml (30.1-25.1)
= 250 cal

Heat absorbed by calorimeter = 250 + 840 = 1090 cal

Ccal = qcal / delta T
= 590 / (30.1-25.1)
= 118 K

The answer is supposed to be 493.24 J/K ... but i am not getting that.
Please someone please show me how to correct this.

Thank you.
 
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Heat absorbed by calorimeter = 250 + 840 = 1090 cal
Woah!

Heat is lost from the hot water to the calorimeter AND the cold water. One cannot at the heat of the hot and cold water.

Try ΔQ(hot) = ΔQ(calorimeter) + ΔQ(cold)
 
Astronuc said:
Woah!

Heat is lost from the hot water to the calorimeter AND the cold water. One cannot at the heat of the hot and cold water.

Try ΔQ(hot) = ΔQ(calorimeter) + ΔQ(cold)

I tried doing that and the answer is 118 (which is still INCORRECT)...i wrote plus there where it should be minus.
 
Last edited:
Show your detailed work then.
 
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