A system releases 647 kJ of heat and does 150 kJ of work on the surroundings.
What is the change in internal energy of the system?
E = dH + work
E = - 647 kJ + (-150 kJ) = ?
To calculate the change in internal energy of the system, we need to use the first law of thermodynamics, which states that the change in internal energy (ΔU) is equal to the heat added to the system (q) minus the work done by the system (w).
Mathematically, the equation is:
ΔU = q - w
Given that the system releases 647 kJ of heat (q = -647 kJ) and does 150 kJ of work on the surroundings (w = -150 kJ), we can substitute these values into the equation:
ΔU = -647 kJ - (-150 kJ)
= -647 kJ + 150 kJ
= -497 kJ
Therefore, the change in internal energy of the system is -497 kJ.