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Const@ntine
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Homework Statement
Vapors of 100 C is added to an ice cube of 0 C.
How much of the ice cube has melted and what's the final temperature if the masses of the steam and the ice cube are 10.0 g & 50.0 g respectively?
Homework Equations
Lw = 3.33 x 105 J/kg
cw = 4186 J/kg*C
Q = m*c*ΔΤ
Q = L*Δm
Qcold = -Qhot
The Attempt at a Solution
To be honest this part of the chapter has me confused a bit because I'm not sure what to do each time and what rules to follow. For example, I looked back to an exercise about vapors being added to water, and it had the vapors being liquified, then having their temp lowered, the water getting its temp raised, and then going with the Qcold = - Qhot equation to find the final temperature.
Here though, I've tried all the combinations I can think of, and I still can't find the right answer.
1) First, I tried with the vapors being liquified and having their temp lowered, the ice cube being liquified as well and having its temp raised, and then putting that in the Qc = -Qh. Wrong result.
2) Then I tried with just the vapors getting liquified not the ice cube. Wrong again.
3) Then I figured it happens instantly, and went straight for Qc = - Qh. Wrong one more time.
Generally I don't understand how I can use my data to find both unknown factors. I don't know how to approach this, because I'm not sure if I should assume that the vapors and/or the cube start gettingliquified first and then do the "exchange" though Qc = -Qh, or if its happens instantly. Furthermore, I don't see how I can find two unknown variables from just one equation.
Any help is appreciated!