Question

Which one is INCORRECT statement?

• A. In an isochoric process, volume remains constant
• B. In an adiabatic process, there is a heat exchange with the surrounding
• C. In an isobaric process, pressure remains constant
• D. In an isothermal process, temperature remains constant
• E. In a cyclic process, the change in internal energy is zero

Hint:

Adiabatic = No heat transfer ($Q=0$).

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
We need to identify the incorrect statement among five descriptions of different thermodynamic processes. This requires knowing the definitions of these key processes.
Step 2: Detailed Explanation:
Let's analyze each statement: - (A) Isochoric process: The prefix "iso-" means constant, and "choric" relates to volume. An isochoric process is indeed one where the volume remains constant (\( \Delta V = 0 \)). This statement is correct. - (B) Adiabatic process: The term "adiabatic" means there is no heat exchange between the system and its surroundings. The system is thermally insulated. The statement says there is a heat exchange, which is the opposite of the definition. From the first law of thermodynamics (\( \Delta U = Q - W \)), for an adiabatic process, \( Q=0 \). This statement is incorrect. - (C) Isobaric process: "Baric" relates to pressure. An isobaric process is one where the pressure remains constant (\( \Delta P = 0 \)). This statement is correct. - (D) Isothermal process: "Thermal" relates to temperature. An isothermal process is one where the temperature remains constant (\( \Delta T = 0 \)). For an ideal gas, this also means the change in internal energy is zero (\( \Delta U = 0 \)). This statement is correct. - (E) Cyclic process: A cyclic process is one where the system returns to its initial state at the end of the process. Since internal energy (U) is a state function, if the initial and final states are the same, the change in internal energy must be zero (\( \Delta U = 0 \)). This statement is correct. Step 3: Final Answer:
The incorrect statement is (B).