Specific Heat Under Const. Press. vs. Const. Vol.

[Alex Nguyen 3I]

Would heat be used to raise the pressure under constant volume, like how some of it is used to raise the volume under constant pressure as opposed to the temperature?

[Nitin Joseph]

Yes. Since gases have a tendency to expand (increase in volume) when heated, if you don't allow them to expand (by keeping the volume constant), the pressure will increase.
For example, this is why balloons explode when exposed to a flame, because the volume of the balloon is kept constant, but the pressure increases due to heating, leading to BOOM.

[Alex Nguyen 3I]

Does the amount of heat used to change the volume under constant pressure equal the amount of heat used to change the pressure under constant volume for liquids and solids? Is that why their heat capacity is the same under constant pressure or constant volume?