How to Calculate Final Temperature in a Water and Aluminum System?

AI Thread Summary
To calculate the final temperature (Tf) in a system with boiling water and an aluminum pan, the heat exchange equation m1C1(Tf - T_initial_water) + m2C2(Tf - T_initial_aluminum) = 0 is used. Here, m1 and m2 represent the masses of water and aluminum, respectively, while C1 and C2 are their heat capacities. Rearranging the equation leads to Tf = (m1C1*T_initial_water + m2C2*T_initial_aluminum) / (m1C1 + m2C2). The final temperature is determined by balancing the heat lost by the water with the heat gained by the aluminum. This approach effectively resolves the problem of finding Tf in the given system.
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Homework Statement



160 grams of boiling water (temperature 100° C, heat capacity 4.2 J/gram/K) are poured into an aluminum pan whose mass is 950 grams and initial temperature 26° C (the heat capacity of aluminum is 0.9 J/gram/K).
(a) After a short time, what is the temperature of the water?



Homework Equations



ΔE = ΔKsys + Δ(Msysc^2) + ΔUsys + ΔEint = Wsurr + Q

Wsurr + Q = 0 because the surroundings aren't effecting the problem, and ΔEint isn't changing.

ΔEint = 0

So...

m1C1*ΔT + m2C2*ΔT = 0

m1C1(Tf - 373.15K) + m2C2(Tf - 299.15K) = 0




From there I don't know what to do. I know I have to solve for Tf, but I guess my problem is I don't know how to solve for Tf.

I know that Tf is the same for both of them, but that doesn't really help me solve for it. I'm probably just not thinking straight right now.

The Attempt at a Solution



Couldn't get an answer because I can't figure out how to solve for Tf.
 
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This looks right, m1C1(Tf - 373.15) + m2C2(Tf - 299.15) = 0
so rearranging terms this gives Tf(m1C1-m2C2) = 373.15m 1C1-299.15 m2C2

Tf = (373.15 m1C1-299.15 m2C2)/(m1C1-m2C2)
 
It took a while, but it actually equals:

Tf=373.15m1c1+299.15m2c2/m2 + c2
 
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