## Heating curve

Althea Zhao 1B
Posts: 101
Joined: Mon Jun 17, 2019 7:24 am

### Heating curve

How is the formula for enthalpy with a change in temperature along a heating curve different from the formula for enthalpy at temperature plateaus?

KaleenaJezycki_1I
Posts: 127
Joined: Sat Aug 17, 2019 12:18 am
Been upvoted: 2 times

### Re: Heating curve

For the sloped lines in a heating curve ( the solid, or liquid is heating up) for the straight horizontal lines the phase change is occurring. When calculating the sloped lines you use q=mCDeltaT but when you are at a phase change ( straight line), you use n*DeltaHfusion

Juliana Chopelas 1A
Posts: 50
Joined: Sat Aug 24, 2019 12:16 am

### Re: Heating curve

When a phase change is happening you will use q=mdeltah or q=ndeltah depending on whether you are given mass or moles. When the substance is heating up or the diagonal line on the curve, you will used q=mcdeltaT or q=ncdeltaT once again depending on whether you are given moles or mass.

Charysa Santos 4G
Posts: 107
Joined: Wed Sep 18, 2019 12:21 am

### Re: Heating curve

Phase changes correlate to the plateau of a heating curve, and there, you can use q = mΔh if you are given mass or q = nΔh if you are given moles. If you are calculating the diagonal/rise in temperature, you will use q = mCΔT or q = nCΔT.

Kennedi2J
Posts: 101
Joined: Wed Sep 18, 2019 12:20 am

### Re: Heating curve

There technically is no temperature change at the plateaus where phase changes occur (i.e. melting is 0 degrees---> 0 degrees). For phase changes you use q=m(delta H) and for a temperature change you use q= mCAT.

Alondra
Posts: 36
Joined: Tue Feb 26, 2019 12:15 am

### Re: Heating curve

Phase changes --> use q=m(delta H)

Temperature change --> use q= mCAT
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