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### What is the difference between delta H and q?

Posted: Tue Jan 29, 2019 1:44 pm
delta H is the change in heat; the measure of heat; isn't q also a measure of heat? what is the difference between delta H and q?

### Re: What is the difference between delta H and q?

Posted: Tue Jan 29, 2019 2:07 pm
Delta H is enthalpy, so it is just the measurement of change in heat *at constant pressure*. So if the reaction takes place at constant pressure, then delta H=q (enthalpy=q).

### Re: What is the difference between delta H and q?

Posted: Tue Jan 29, 2019 4:13 pm
Enthalpy change (delta h) only applies to reactions done at constant pressure and it is the state of a system while it contains a certain amount of heat. Heat (q) is just the energy that causes those changes and is the energy transferred as a result of a temperature difference.

### Re: What is the difference between delta H and q?

Posted: Tue Jan 29, 2019 8:07 pm
q just refers to heat while delta h refers to the change of heat within a specific reaction under standard and constant pressure