Question

The first law of thermodynamics is related to:

• A. Entropy
• B. Enthalpy
• C. Conservation of energy
• D. Free energy

Hint:

Always link the first law of thermodynamics with conservation of energy. It does not describe entropy or spontaneity—those are covered by the second and third laws.

Answer 1

The Correct Option is C

The first law of thermodynamics states that energy can neither be created nor destroyed; it can only be transformed from one form to another.
Mathematically, it is represented as: \[ \Delta U = Q - W \] Where:
\(\Delta U\) = change in internal energy
\(Q\) = heat added to the system
\(W\) = work done by the system
This law emphasizes the principle of conservation of energy. It ensures that the total energy of an isolated system remains constant. Heat added to the system contributes either to increasing its internal energy or to doing work.
Hence, the first law is fundamentally a statement of the conservation of energy.