Specific heat and latent heat of fusion

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To solve the problem of determining the mass of remaining ice after adding it to tea, the specific heat capacity of water and the latent heat of fusion must be applied. The calculations show that the heat lost by the tea as it cools from 35°C to 15°C is 18,418.4 J. This energy is used to melt the ice and then raise the temperature of the resulting water. The initial calculation incorrectly suggests more mass than started due to not accounting for the temperature increase of the melted ice. Properly including this step will yield the correct mass of remaining ice.
rahndezvous
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Hi this is my first post and I'm stumped on my last HW problem, so I'm open to suggestions or solutions.

1. A jar of tea is placed in sunlight until it reaches an equilibrium temperature of 35°C. In an attempt to cool the liquid, which has a mass of 220 g, 112 g of ice at 0.0°C is added. At the time at which the temperature of the tea is 15°C, determine the mass of the remaining ice in the jar. Assume the specific heat capacity of the tea to be that of pure liquid water.

_______grams




2. specific heat of water 4186 J/Kg*C
Latent heat of fusion for water 3.33*10^5 J/Kg
Q=Cp*m*/\T
Q=m*Lf
m=Q/Lf




4186 Cp*.22 Kg*20 C=18418.4
18418.4/3.33*10^5 Lf = .5531
.5531*1000=553.1g


Why do I get more than i started with?
 
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please reply within the next 9.5 hours thanks :)
 
rahndezvous, don't forget that once you've melted the ice, you then need to increase the temperature of the melted ice to 15oC.
 
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