Temperature and Heat - what am i doing wrong?

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To convert 9 kg of ice at 0°C to steam at 100°C, three processes must occur: melting the ice, heating the water, and vaporizing the steam. The heat required to melt the ice is calculated using the latent heat of fusion (lf), which is 79500 cal/kg, resulting in 715500 cal for 9 kg of ice. Next, the water must be heated from 0°C to 100°C using the specific heat capacity (c) of water, which is 1000 cal/kg°C, requiring an additional 900000 cal. Finally, to convert the water at 100°C to steam, the latent heat of vaporization (lv) is used, amounting to 4860000 cal for 9 kg. The total heat needed is 6465000 cal, or 6465 kcal.
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Homework Statement



lf = 79500 cal/kg ,
lv = 5.4 × 105 cal/kg ,
c = 1000 cal/kg ◦ C.

9 kg of ice at 0◦C is converted to steam at
100◦C.
How much heat is needed? Answer in units
of kcal.


Homework Equations



q=mct

The Attempt at a Solution



100*9kg + 79.5 + 540 = 1519.5

I am getting this wrong I don't know why
 
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Can you explain what each term in your attempted solution means? They don't seem to make sense. They don't match the numbers given in the problem? It would be helpful if you explained what you were doing.

Also, what three processes (involving heat) have to occur in order to get from ice at 0C to steam at 100C?
 
If lf is 79500 cal/kg, and you have 9 kg of ice, then how much energy is required to melt the ice?

Hint: the answer it not 79.5.

Also, what is the value of c for water?
 
I got the answer! Thanks for your help.
 
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