Calculating Heat of Fusion of Ice from Data

AI Thread Summary
The discussion focuses on calculating the heat of fusion of ice using energy data from heating ice at -10°C to -1°C and then converting it to water. It is established that the specific heat of ice is half that of water, which is 4.2 kJ/(kg °C). The initial equations set up to calculate energy (Q) are corrected, emphasizing that the energy required to convert ice to water must include the heat of fusion (L). The key correction made is that the total energy equation should account for both the heating of ice and the phase change to water. This highlights the importance of accurately incorporating all energy components in thermodynamic calculations.
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Homework Statement



A piece of ice at-10 centigrade is heated to -1 C using a certain quantity of energy. Then another 20 times as much energy is necessary to finally obtain water. Using that the specific heat of ice is half of the specific heat of 4.2 kJ/(kg oC) of water, determine the heat of fusion of ice from the above measurement data.


Homework Equations


Q=mct
Q=mL


The Attempt at a Solution


Assuming heat to be Q
and mass m

Q=mct
Q=m x 2.1 x 9

and also

20Q = m x 2.1 x 1
Equating
m x 2.1 x 9 x 20 = m x 2.1 x 1

(This is wrong since Fusion of ice didnt come into picture... so any help appreciated)
(Also this is not a homework question... just one which I saw in some book )
 
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The problem says 20 much more energy is required to get WATER. So your second equation:

20Q = m*2.1*1 is wrong, it's supposed to be:

20Q = m*2.1*1 + mL

-Tusike
 
Thanks a lot Tusike .
 
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