Heating Curve Calculation Confusion

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torialmquist1F
Posts: 49
Joined: Sat Jul 22, 2017 3:00 am

Heating Curve Calculation Confusion

Postby torialmquist1F » Sun Jan 21, 2018 6:03 pm

If there is a question where we have to convert ice to water vapor, do we have to use MCdeltaT twice to account for the temp change between the solid to melting point and also from the melting point to the boiling point? So would it be MCdeltaT+phase change+MCdeltaT+phase change

vicenteruelos3
Posts: 42
Joined: Fri Sep 29, 2017 7:07 am

Re: Heating Curve Calculation Confusion

Postby vicenteruelos3 » Sun Jan 21, 2018 6:21 pm

it depends on the starting temperature of the ice and the final temperature of the water vapor

if the starting temp of ice is less than 0 and the final temp of water vapor is over 100 degrees celcius
then you would use MCdeltaT three times
once to go from <0 to 0, phase change, then to go from 0 to 100, phase change, and finally to go from 100 to to >100

if the starting temp of the ice is exactly 0 and the final temp of water vapor is exactly 100
then you would use MCdeltaT once
phase change, MCdeltaT from 0 to 100, and phase change

it would be MCdeltaT+phase change+MCdeltaT+phase change
if the starting temp of ice was less than 0 and the final temp of water vapor was exactly 100 degrees celcius

Wenxin Fan 1J
Posts: 53
Joined: Thu Jul 13, 2017 3:00 am

Re: Heating Curve Calculation Confusion

Postby Wenxin Fan 1J » Sun Jan 21, 2018 6:32 pm

When temperature changes for a substance use the equation q=mCdeltaT and when the desired or required temperature is met and the substance changes phase use the values for delta H of vaporization or melting to find the heat . Add all the values together

AnuPanneerselvam1H
Posts: 52
Joined: Fri Sep 29, 2017 7:07 am

Re: Heating Curve Calculation Confusion

Postby AnuPanneerselvam1H » Sun Jan 21, 2018 11:36 pm

This depends on the initial and final temperatures of the system. If the system goes from -10 degrees Celsius to 50 degrees Celsius, you need to calculate
mCdeltaT for -10 degrees to 0 degrees + phase change from ice to liquid + mCdeltaT for 0 degrees to 50 degrees


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