Heating Curve Slope and Heat Capacity

[Dahlia Kirov 3A]

Hi!

I understand that a higher heat capacity reflects more energy needed to change the temperature of a substance, but why would requiring more energy to change the temperature of a substance be reflected on a heating curve as having a smaller slope and being less steep?

[Tiffany Wang 3L]

A higher heat capacity would have a smaller slope on a heating curve because it would take more heat added (x-axis) to reach the same temperature (y-axis) as something with a smaller heat capacity. Your reasoning is correct, but I think visualizing it would be more helpful. For example, in the image I attached, the green heating curve for a substance with higher heat capacity would reach 50 degrees only when more heat is added than a substance with lower heat capacity (blue heating curve).

[Bridgette Ryning 1D]

To add on, heat capacity is how much energy it takes to increase one gram (or mol) by 1 degree. So for the substance to go up one degree it might have to absorb more energy hence the slope being less steep (going further across the x axis means more heat added)