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प्रश्न
Write the mathematical expression of the First Law of Thermodynamics for the Isobaric process.
उत्तर
Usually, chemical reactions are carried out in open containers under constant atmospheric pressure. In such reactions, ∆V ≠ 0
∵ ∆U = Q - Pext ∆V ...(1)
Replacing Q by Qp and ∆U by Qp - Pext ∆V in equation (1) gives
Qp = ∆U + Pext ∆V
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