Mix steam with colder water, what is final temp?

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SUMMARY

The final temperature of a mixture of 100 g of steam at 100°C and 1 kg of water at 10°C is calculated using the principles of heat transfer and phase change. The process involves the condensation of steam into water, releasing latent heat, followed by thermal equilibrium between the resulting water and the colder water. The correct calculation shows that the final temperature is 67°C, not 60°C, as initially miscalculated due to a typographical error in the latent heat value used. The equations applied include Q=mL for phase change and Q=mcΔT for temperature change.

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SunshineCat
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Homework Statement


100 g of steam at 100C is mixed with 1 kg of water at 10C. What is the final temperature of the mixture? (in C)
heat capacity of water: cw = 4.186 kJ kg-1 K−1
latent heat of vapourisation for water: Lv = 2256 kJ kg−1
latent heat of fusion for water: Lf = 334 kJ kg−1

Homework Equations


Q=mL
Q=mcΔT

The Attempt at a Solution


I think that there needs to be a phase change of condensation, 0.1kg of 100C steam to 0.1kg of 100C water, so this will be Q=mL and will be an energy loss
The energy lost will go to the colder water
After this, energy will keep flowing from the 100C water to 10C water until they reach the same temperature, energy gain and loss will be Q=mcΔT
I can't seem to get the calculation right, I keep getting 60C when the answer is 67C

ΔQ (steam) = ΔQ(water)
Q=mcΔT = mL + mcΔT
0.1x4.186x(T-100) = 1x4.186x(T-10) - 0.1x225.6
225.6=3.77T
T=60C?
 
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SunshineCat said:
0.1x4.186x(T-100) = 1x4.186x(T-10) - 0.1x225.6

That should be 0.1 * 2256
 
CWatters said:
That should be 0.1 * 2256
Oh yeah, that was a typo I think
 

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