q and delta H

[Harmony Becerra]

Hello, I was wonder if q and delta H are the same thing? Because I see them being use interchangeably.

[Ariel Cheng 2I]

I think q = delta H under constant pressure. I also think that delta H implies constant pressure already so they can be used interchangeably but I am not sure.

[Douglas Nguyen 2J]

q is equal to delta H when pressure is constant.

This gives you:

delta U = delta H - P(delta V)

[Ronald Thompson 1F]

They can be used interchangeably

[paytonm1H]

the definition of enthalpy is the change in heat of a system at constant pressure. so q = deltaH at constant pressure.

[Aurbal Popal]

delta H = delta U + P delta V

when there is a constant pressure,

delta H= q

I think the q comes from the delta U (as delta U= q +w)

Hope this helps.

[lukezhang2C]

So Delta U = q + w = q - PdeltaV, meaning that under constant pressure U = q = delta H. This is where most of the interchangeability comes from as systems with constant pressure appear often in our problems.