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MHT CET202120 Sep 2021Evening ShiftChemistryThermodynamics (C)Actual

Calculate change in enthalpy when 39 ~g acetylene is completely burnt with oxygen and enthalpy of combustion of acetylene is 1300 ~kJ / mol .

Options

  1. A-975 ~kJ
  2. B-650 ~kJ
  3. C-1950 ~kJ
  4. D-1600 ~kJ

Correct answer

C. -1950 ~kJ

Step-by-step solution

aligned & C ₂ H _ 2( ~g ) + 5 2 O _ (2) 2 CO _ ( g ) + H ₂ O _ ( ) ; _ r H ^ =-1300 ~kJ ~mol ⁻¹ & Acetylene & When 26 ~g of acetylene is completely burnt, the change in & enthalpy =-1300 ~kJ & For 39 ~g of acetylene, the change in enthalpy & = -1300 39 26 =-1950 ~kJ aligned

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