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MHT CET202310 May 2023Evening ShiftChemistryThermodynamics (C)Actual

If 8.84 ~kJ heat is liberated for formation of 3 ~g ethane, calculate its _ f H ^ .

Options

  1. A-8.00 ~kJ
  2. B15.0 ~kJ
  3. C30.0 ~kJ
  4. D-88.4 ~kJ

Correct answer

D. -88.4 ~kJ

Step-by-step solution

Formation of ethane: 2 C _ ( s ) +3 H _ 2( ~g ) C ₂ H _ 6( ~g ) ; _ f H ^ = ? Molar mass of C ₂ H ₆=30 ~g ~mol ⁻¹ 3 ~g C ₂ H ₆= 3 30 = 1 10 mol For formation of 1 10 ~mol C ₂ H ₆, 8.84 ~kJ heat is liberated. Formation of 1 ~mol C ₂ H ₆ will liberate 88.4 ~kJ of heat. _ f H ^ of C ₂ H ₆=-88.4 ~kJ

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