## relationship between delta H and q [ENDORSED]

Nick_Kopooshian_3C
Posts: 12
Joined: Fri Jul 22, 2016 3:00 am

### relationship between delta H and q

When is delta H and q interchangeable?

Cindy Flores 2C
Posts: 27
Joined: Wed Sep 21, 2016 2:59 pm

### Re: relationship between delta H and q  [ENDORSED]

Great question, delta H and q are interchangeable only when there is heat under constant pressure.

Jeannie_Kim_1I
Posts: 23
Joined: Fri Jul 15, 2016 3:00 am

### Re: relationship between delta H and q

Delta H is considered a specific type of q. Delta H=qp.

Janice Kim 3I
Posts: 33
Joined: Wed Sep 21, 2016 2:56 pm

### Re: relationship between delta H and q

If pressure is held constant, q will have a subscript p (qp), making it interchangeable with delta H.

Kevin Le 1L
Posts: 17
Joined: Fri Jul 22, 2016 3:00 am

### Re: relationship between delta H and q

Like the others said above, q and delta H are interchangeable only when a system is under constant pressure. However, we can calculate q using delta H during phase changes. q = (mass)(delta H at a phase change).

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