Calculate the standard enthalpy change of following reaction. C ₂ H _ 4( ~g ) +3 O _ 2( ~g ) 2 CO _ 2( ~g ) +2 H ₂ O _ ( ) If _ f H ^ ( C ₂ H ₄ )=-52 ~kJ ~mol ⁻¹ aligned _ f H ^ ( CO ₂ ) & =-390 ~kJ ~mol ⁻¹ _ f H ^ ( H ₂ O ) & =-286 ~kJ ~mo

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Calculate the standard enthalpy change of following reaction. C ₂ H _ 4( ~g ) +3 O _ 2( ~g ) 2 CO _ 2( ~g ) +2 H ₂ O _ ( ) If _ f H ^ ( C ₂ H ₄ )=-52 ~kJ ~mol ⁻¹ aligned _ f H ^ ( CO ₂ ) & =-390 ~kJ ~mol ⁻¹ _ f H ^ ( H ₂ O ) & =-286 ~kJ ~mol ⁻¹ aligned

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Correct answer: B. -1300 ~kJ

The standard enthalpy change, _ r H^ , is calculated using the formula: _ r H^ = n _ f H^ ( products ) - m _ f H^ ( reactants ) Given the reaction C ₂ H _ 4( g ) + 3 O _ 2( g ) 2 CO _ 2( g ) + 2 H ₂ O _ ( ) and the standard enthalpies of formation: _ f H^ ( C ₂ H ₄) = -52 kJ mol ⁻¹ , _ f H^ ( CO ₂) = -390 kJ mol ⁻¹ , _ f H^ ( H ₂ O ) = -286 kJ mol ⁻¹ , with _ f H^ ( O ₂) = 0 . Substituting into the formula: _ r H^ = [2 (-390) + 2 (-286)] - [1 (-52) + 3 0] = [-780 - 572] - [-52 + 0] = -1352 - (-52) = -1300 kJ Final

Calculate the standard enthalpy change of following reaction. C ₂ H _ 4( ~g ) +3 O _ 2( ~g ) 2 CO _ 2( ~g ) +2 H ₂ O _ ( ) If _ f H ^ ( C ₂ H ₄ )=-52 ~kJ ~mol ⁻¹ aligned _ f H ^ ( CO ₂ ) & =-390 ~kJ ~mol ⁻¹ _ f H ^ ( H ₂ O ) & =-286 ~kJ ~mol ⁻¹ aligned

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