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MHT CET202020 Oct 2020Morning ShiftChemistryThermodynamics (C)Actual

The heat of Combustion of acetaldehyde to carbon dioxide and water is -1172 ~kJ mol ⁻¹ . Calculate amount of heat liberated when 66 ~g of acetaldehyde were completely oxidised ? (at. mass C =12, H =1,0=16 )

Options

  1. A1758 ~kJ
  2. B2344 ~kJ
  3. C6600 ~kg
  4. D1172 ~kJ

Correct answer

A. 1758 ~kJ

Step-by-step solution

CH ₃ CHO +2.5 O ₂ 2 CO ₂+2 H ₂ O H =-1172 ~kJ ~mol ⁻¹ For 44 ~g of CH ₃ CHO , H =-1172 ~kJ ~mol ⁻¹ 66 ~g of CH ₃ CHO , H = -1172 66 44 =-1758 ~kJ ~mol ⁻¹ The amount of heat liberated when 66 ~g of acetaldehyde were completely oxidised is 1758 ~kJ ~mol ⁻¹

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