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NEETChemistryThermodynamics (C)

An ideal gas undergoes a thermodynamic process from state A to state B. The process is represented on a pressure-volume (P-V) diagram as a curve where pressure is inversely proportional to volume ( P 1 V ). Which of the following is correct for the changes in internal energy ( U ) and enthalpy ( H ) of the gas during this process?

Options

  1. AU = 0 , H = 0
  2. BU > 0 , H > 0
  3. CU = 0 , H > 0
  4. DU < 0 , H < 0

Correct answer

A. U = 0 , H = 0

Step-by-step solution

For an ideal gas, the condition P 1 V implies that PV = constant . According to the ideal gas equation, PV = nRT . If PV is constant, the temperature T must be constant, meaning the process is isothermal ( T = 0 ). For an ideal gas, both internal energy ( U ) and enthalpy ( H ) are functions of temperature only. Since there is no change in temperature, the change in internal energy ( U ) and the change in enthalpy ( H ) are both zero. Therefore, U = 0 and H = 0 . Answer: U = 0 , H = 0

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