derive the relationship between delta H and delta U for an ideal gas .explain each term involved in the equation.
derive the relationship between delta H and delta U for an ideal gas .explain each term involved in the equation.
The relationship between delta H and delta U for an ideal gas is:
delta H = delta U + P delta V
delta H = change in enthalpy of the system (H2-H1)
delta U = change in internal energy of the system (U2-U1)
P = pressure
delta V = change in the volume of the system (V2-V1)
Derivation
We know that work done w = -P(V2-V1)
delta U = q+w (q is the qty of heat transferred from the surroundings to the system )
delta U = q - P(V2-V1)
U2-U1 = q - P(V2-V1)
q = (U2 +PV2)- (U1+PV1)
q = (U2-U1) + P(V2-V1)
The quantity U+PV is known as enthalpy of the system and denoted by H
i.e H = U+PV As U, Hand V are definite properties and depends upon the states(initial and final) of the system.
q = H2-H1=delta H
Therefore delta H = delta U + P delta V
The relationship between delta H and delta U for an ideal gas is:
delta H = delta U + P delta V
delta H = change in enthalpy of the system (H2-H1)
delta U = change in internal energy of the system (U2-U1)
P = pressure
delta V = change in the volume of the system (V2-V1)
Derivation
We know that work done w = -P(V2-V1)
delta U = q+w (q is the qty of heat transferred from the surroundings to the system )
delta U = q - P(V2-V1)
U2-U1 = q - P(V2-V1)
q = (U2 +PV2)- (U1+PV1)
q = (U2-U1) + P(V2-V1)
The quantity U+PV is known as enthalpy of the system and denoted by H
i.e H = U+PV As U, Hand V are definite properties and depends upon the states(initial and final) of the system.
q = H2-H1=delta H
Therefore delta H = delta U + P delta V
