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A diatomic gas ( =1.4) does 100 J of work when it is expanded isobarically. Then the heat given to the gas _ _ _ _ J.

Correct answer

350

Step-by-step solution

For an isobaric process, the first law gives: Q = U + W . For a diatomic gas with = 1.4 , we have C_V = 5 2 R and C_P = 7 2 R . Since W = nR T = 100 J for isobaric expansion, the change in internal energy is: U = nC_V T = 5 2 nR T = 5 2 100 = 250 J. Therefore, Q = 250 + 100 = 350 J.

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