In an isobaric process, 600 J of heat is supplied, and the system does 200 J of work. What is Δ U?
At constant pressure, Δ H = qp = 600 J, w = -200 J (work done by system). Δ U = q + w = 600 - 200 = 400 J.
Ref: NCERT Class 11 Chemistry > Chapter 5: Thermodynamics > Topic: Thermodynamic Terms - System Surroundings and Types of Systems