Do both H (enthalpy) and ∆H, or ∆H alone have a physical significance?

Question

My chemistry teacher said that H (enthalpy) alone has no physical significance it is ∆H or change in enthalpy that has a physical significance. But my book says that both have a significance and H alone represents the total heat content of the body. Thus I am in a confusion, please help me.

related http://chemistry.stackexchange.com/questions/19541/why-it-is-not-possible-to-find-absolute-value-of-internal-energy — Mithoron, Mar 22 '17 at 22:57

score 1 · Answer 1 · answered Mar 22 '17 at 17:26

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Offcourse H and ∆H have physical significance. H represents the enthalpy of a system. Enthalpy refers to the sum of the internal energy of a system plus the product of the system's pressure and volume.

The ∆ symbol is used to represent change. Therefore, ∆H represents the change in enthalpy of a system in the reaction. So your book is completely correct.

answered Mar 22 '17 at 17:26

Yb609

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That being said, the teacher is right too (in a way). We pretty much never know absolute enthalpy of anything. Arguably, it may not even be well-defined. – Ivan Neretin Mar 22 '17 at 18:04
@IvanNeretin I completely agree with your point. – jyoti proy Mar 22 '17 at 18:12
@IvanNeretin Ya thats true. Agreed with you – Yb609 Mar 22 '17 at 18:13

Do both H (enthalpy) and ∆H, or ∆H alone have a physical significance?

1 Answers1