Chemistry I / The First Law of Thermodynamics
Practice question · Numerical answer

A system absorbs 150 J of heat and has 60 J of work done on it. Compute the change in internal energy, in joules.

Hints
  1. Both heat absorbed and work done on the system are positive.
  2. Compute 150 + 60.
Show the answer

210

Why

ΔU=q+w=150+60=210\Delta U = q + w = 150 + 60 = 210 J. Both terms are positive because both represent energy entering the system across the boundary.

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