Final answer:
It is not possible to determine from the final internal energy of a system whether the change was caused by heat transfer, work, or a combination. The properties depend solely on internal energy, not how it was changed. The correct option is B.
Step-by-step explanation:
To answer the question: Is it possible to determine whether a change in internal energy is caused by heat transferred, by work performed, or by a combination of the two? The answer is No.
Heat and work both change the internal energy of the substance, and the properties of the sample only depend on the internal energy. Hence, it is impossible to tell whether heat was added to sample A or B just by observing the final state of the internal energy.
The First Law of thermodynamics tells us that the change in internal energy (ΔU) during any process is equal to the heat (Q) added to the system minus the work (W) done by the system: ΔU = Q - W.
However, without additional information, we cannot discern the individual contributions of Q and W to the change in internal energy solely based on the final state after the energy change.