At constant pressure (∆P=0)

Than, Enthalpy

∆H=∆U+∆(PV)

∆H=∆U+P∆V+V∆P; But as (∆P=0)

∆H=∆U+P∆V

But if the Volume is constant (∆V=0)

Than the equation becomes

∆H=∆U+V∆P

What does this Equation implies and what is it's application?

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Solution

The first equation can be used in a situation where the pressure is kept constant and all other quantities are varied. The second equation can be used in a situation where the volume is kept constant.

So we can use these formula directly for calculating change in enthalpy just by reading the question and understanding the conditions given.

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At constant pressure (∆P=0) Than, Enthalpy ∆H=∆U+∆(PV) ∆H=∆U+P∆V+V∆P; But as (∆P=0) ∆H=∆U+P∆V But if the Volume is constant (∆V=0) Than the equation becomes ∆H=∆U+V∆P What does this Equation implies and what is it's application?

At constant pressure (∆P=0)

Than, Enthalpy

∆H=∆U+∆(PV)

∆H=∆U+P∆V+V∆P; But as (∆P=0)

∆H=∆U+P∆V

But if the Volume is constant (∆V=0)

Than the equation becomes

∆H=∆U+V∆P

What does this Equation implies and what is it's application?