The standard heat of formation of carbon disulphide (l) given that the standard

The Standard Heat Of Formation Of Carbon Disulphide L Given Chemistry QuestionThe Standard Heat Of Formation Of Carbon Disulphide L Given Chemistry Question

The standard heat of formation of carbon disulphide (l) given that the standard heat of combustion of carbon(s) , sulphur(s) and carbon disulphide(l) are -393.3, -293.72 and -1108.76 kJ mol⁻¹ respectively is

Options

(a) 128.02 kJ mol⁻¹
(b) 12.802 kJ mol⁻¹
(c) -128.02 kJ mol⁻¹
(d) -12.802 kJ mol⁻¹

Correct Answer:

128.02 kJ mol⁻¹

Explanation:

(i) C(s) + O₂(g) → CO₂(g); ΔH₁ = -393.3 kJ.
(ii) S(s) + O₂(g) → SO₂(g); ΔH₂ = -293.72 kJ.
(iii) CS₂(l) + 3O₂(g) → CO₂ + 2SO₂ ; ΔH₃ = -1108.76 kJ.
On adding (i) and (ii) and subtracting (iii), we get,
C(s) + 2S(s) → CS₂(g), ΔH = -393.3 + 2 (-293.72) + 1108.76 = +128.02 kJ mol⁻¹.

AddThis Website Tools
admin:

Related Questions

  1. The wavelength correspending to maximum enregy for hydrogen is 91.2 nm
  2. If an electron has spin quantum number of +1/2 and a magnetic quantum number
  3. The preparation of ethene from ethanol can be described as
  4. For an endothermic reaction the value of ΔS is positive.The reaction is
  5. The number of unpaired electron in Mn²⁺ is