Heating curve

[Althea Zhao 1B]

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]

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]

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]

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]

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]

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

Temperature change --> use q= mCAT