How to Calculate Heat Needed to Convert Ice to Steam at Different Temperatures?

AI Thread Summary
To calculate the heat needed to convert 150g of ice at -10°C to steam at 110°C, multiple steps and equations are required. The relevant formulas include Q = mcΔT for temperature changes and Q = mLf for phase changes. Initial calculations provided by the user yield incorrect results, indicating that not all necessary steps were included. The correct approach involves summing the heat required for warming the ice, melting it, heating the resulting water, converting it to steam, and then heating the steam. The final answer should total 109.5 kcal, highlighting the need for a comprehensive calculation process.
domyy
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Homework Statement



Calculate the amount of heat to be added to warm 150g of ice from -10celsius to produce steam at 110C?

Homework Equations



I believe some relevant equations would be :
Q= mcdeltat
Q= mlf

I also have some values as:

Cice= 0.5 Cal/gcelsius
Lf= 80 Cal/g

C water= 1.0 Cal/gC

Steam= 0.5cal/gC
Lv = 540cal/g

The Attempt at a Solution



My attempt is wrong. I just know the answer, but I want to learn how to get to it. Thank you all in advance!
 
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hi domyy! :wink:

show us your full calculations, and then we'll see what went wrong, and we'll know how to help! :smile:
 
What did is wrong. I tried something simple but there's probably more that I do not know.
I did:

Q = 150g . 0.5 Cal/gC. 100C = 7500

Also tried,

Q= mlf = 150g . 80 Cal/g = 12,000

But I know the answer is 109.5 kcal.
 
domyy said:
What did is wrong. I tried something simple but there's probably more that I do not know.
I did:

Q = 150g . 0.5 Cal/gC. 100C = 7500

Also tried,

Q= mlf = 150g . 80 Cal/g = 12,000

But I know the answer is 109.5 kcal.

sorry, i can't follow that

you seem to have left some things out

can you please write it out properly?
 
Q = 150g x 0.5cal/gC x 100C = 7500

C= Celsius

Q = mLf = 150g x 80 Cal/g = 12,000

But it's wrong. The answer is 109.5 kcal. I need to know the formulas or steps I am missing. The problem is more than that. I believe I am supposed to find several values through equations and sum them.
 
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