# Change in Enthalpy Calculator, Formula, Joules Calculation

## Change in Enthalpy Calculator:

Enter the values of change in internal energy, ∆U(J), constant pressure, P(Pa), change in volume, ∆V(m3) to determine the value of Change in enthalpy, ∆H(J).

 Enter Change in Internal Energy: J Enter Constant Pressure: Pa Enter Change in Volume: m3 Result – Change in Enthalpy: J

## Change in Enthalpy Formula:

Change in enthalpy, ∆H(J) in joules is calculated by summing the change in internal energy, ∆U(J) in joules, constant pressure, P(Pa) in Pascals and then multiply by the change in volume, ∆V(m3) in cubic metres.

Change in enthalpy, ∆H(J) = ∆U(J) + P(Pa) * ∆V(m3)

∆H(J) = change in enthalpy in joules, J.

∆U(J) = change in internal energy in joules, J.

P(Pa) = constant pressure in Pascals, Pa.

∆V(m3) = change in volume in cubic metres, m3.

### Change in Enthalpy Calculation:

1. Finding Change in Enthalpy:

Given: ∆U(J) = 500J, P(Pa) = 101.3k.Pa, ∆V(m3) = 0.002m3.

Change in enthalpy, ∆H(J) = ∆U(J) + P(Pa) * ∆V(m3)

∆H(J) = 500 + 101.3 * 103 * 0.002

∆H(J) = 500 + 202.6

∆H(J) = 702.6J.

1. Finding Change in Internal Energy:

Given: ∆H(J) = 1500J, P(Pa) = 101.3k.Pa, ∆V(m3) = 0.003m3.

Change in enthalpy, ∆H(J) = ∆U(J) + P(Pa) * ∆V(m3)

∆U(J) = ∆H(J) – P(Pa) * ∆V(m3)

∆U(J) = 1500 – 101.3 * 103 * 0.003

∆U(J) = 1196.1J.