How Much Energy Is Needed to Convert Ice at -108°C to Water Vapor at 1108°C?

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To convert 10.0 g of ice at -108°C to water vapor at 1108°C, the total energy required is calculated using specific heats and heats of fusion and vaporization. The initial calculations yielded 50.43 kJ, which did not match any multiple-choice answers provided. Participants suggested that either the problem statement might contain errors or the calculations need re-evaluation. Despite checking the values, the original poster found no discrepancies. Ultimately, the closest correct answer chosen was in the 30 kJ range.
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How much energy in kilojoules is required to convert 10.0 g of ice at -108 to water vapor at 1108°C? Specific heats are 2.09 J/g K for both ice and water vapor, and 4.18 J/g K for liquid water. Heats of vaporization and fusion are 2260 and 335 J/g.

This is what I did:
10g*108C*2.09J/g K + 10g * 335J/g + 10g*100C * 4.18 J/g K + 10g * 2260 J/g + 1008C * 10g * 2.09 J/g K= 50434.4 J =50.43 kJ

This question is a multiple choice, and there is no such choice, so this answer must be wrong. Unfortunately, I really don't know what is wrong with that.

I only the total energy is equal to the heat required to change the -108c ice to 0 C; then plus the energy require to melt the ice and then so far and so on...
 
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Well, i find your answers convincing though I have not claculated exactly. yo have missed no equation.
 
vaishakh said:
Well, i find your answers convincing though I have not claculated exactly. yo have missed no equation.
I don't think I missed any equation,(maybe there are, but I really can not think of one), and there is no mistake in the calculation.
 
zhen said:
question:
(snip)2.09 J/g K for both ice and water vapor, (snip)

You'll want to "check" this value. Either the problem statement included incorrect information, or you've misread something somewhere.
 
Bystander said:
You'll want to "check" this value. Either the problem statement included incorrect information, or you've misread something somewhere.
i check it, there is nothing wrong.
so... i think there is something wrong in the question.
I choose the closest answer which is 30 somthing, and that is correct...
 
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