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MHT CET202521 Apr 2025Morning ShiftChemistryThermodynamics (C)Actual

Calculate the work done in following reaction at 27^ C . 4 SO _ 2( ~g ) +2 O _ 2( ~g ) 4 SO _ 3( ~g ) , ( R =8 314 ~J ~K ⁻¹ ~mol ⁻¹ )

Options

  1. A4988.4 ~J
  2. B2494.2 ~J
  3. C1247.1 ~J
  4. D3741.3 ~J

Correct answer

A. 4988.4 ~J

Step-by-step solution

Work done in the reaction is calculated using the formula for constant temperature gas-phase reactions: W = - n_g RT . The balanced equation 4 SO _ 2( g ) + 2 O _ 2( g ) 4 SO _ 3( g ) shows a net decrease of 2 moles of gas, giving n_g = 4 - 6 = -2 mol . At T = 300 K with R = 8.314 J K⁻¹ mol⁻¹ , the work is: W = -(-2) 8.314 300 = 4988.4 J The positive value indicates work is done on the system. This matches option A. Final answer: A

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