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The enthalpies of combustion of C(graphite) and C(diamond) are -393.8 and -395.3 ~kJ ~mol ⁻¹ respectively. The enthalpy of conversion of C (graphite) to C (diamond) is

Options

  1. A-12.5 ~kJ ~mol ⁻¹
  2. B-789.1 ~kJ ~mol ⁻¹
  3. C79.0 ~kJ ~mol ⁻¹
  4. D1.5 ~kJ ~mol ⁻¹

Correct answer

D. 1.5 ~kJ ~mol ⁻¹

Step-by-step solution

aligned & eq ^ n 1 . . C ( graphite )+ O ₂( ~g ) CO ₂( ~g ) H ₁=-393.8 KJ mol & eq ^ n 2 . . C ( diamond )+ O ₂( ~g ) CO ₂( ~g ) H ₂=-395.3 KJ mol & eq ^ n 1- eq ^ n 2 = H ₁- H ₂ & =-393.8-(-395.3) & =1.5 KJ mol aligned

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