Heating Curve Calculation Confusion
Moderators: Chem_Mod, Chem_Admin
-
- Posts: 49
- Joined: Sat Jul 22, 2017 3:00 am
Heating Curve Calculation Confusion
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
-
- Posts: 42
- Joined: Fri Sep 29, 2017 7:07 am
Re: Heating Curve Calculation Confusion
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
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
-
- Posts: 53
- Joined: Thu Jul 13, 2017 3:00 am
Re: Heating Curve Calculation Confusion
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
-
- Posts: 52
- Joined: Fri Sep 29, 2017 7:07 am
Re: Heating Curve Calculation Confusion
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
mCdeltaT for -10 degrees to 0 degrees + phase change from ice to liquid + mCdeltaT for 0 degrees to 50 degrees
Return to “Phase Changes & Related Calculations”
Who is online
Users browsing this forum: No registered users and 6 guests