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sachin123
Apr12-11, 04:45 AM
what is the difference between delta H and q?
delta H = delta U + P(delta V)
so,
delta H = delta U -W

delta U=q + W
so,
q=delta U - W

So now is there a difference between the two at all?
Why then 2 separate quantities?
Thank You

Mapes
Apr12-11, 06:40 AM
delta H = delta U + P(delta V)

You fixed P to get this expression, so you're no longer looking at the most general case. Does this help answer your question?

sachin123
Apr12-11, 08:15 AM
Yes it does.
So only when the pressure is kept constant,the heat absorbed will become equal to the enthalpy change right?
Thanks Mapes