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NEETChemistryThermodynamics (C)

In the context of pressure-volume work, what does the external pressure (pex) represent?

Options

  1. AThe pressure of the gas inside the cylinder
  2. BThe pressure exerted by the piston
  3. CThe pressure of the surroundings
  4. DThe pressure of the system

Correct answer

C. The pressure of the surroundings

Step-by-step solution

In pressure-volume work, the external pressure (pex) represents the pressure of the surroundings that acts on the system.

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