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MHT CET2018ChemistryThermodynamics (C)

Which of the following equations represents the first law of thermodynamics under isobaric conditions?

Options

  1. AΔ U = q - p e x ⋅ Δ V
  2. Bq = Δ U
  3. CΔ U = w
  4. Dw = - q

Correct answer

A. Δ U = q - p e x ⋅ Δ V

Step-by-step solution

Δ U = q + w ⇒ q + - p e x · Δ V ∵ w = - p e x · Δ V Δ U = q - p e x · Δ V

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