JEE Main202524 Jan 2025Evening ShiftChemistryThermodynamics (C)Actual
aligned & S ( ~g )+ 3 2 O ₂( ~g ) SO ₃( ~g )+2 x kcal & SO ₂( ~g )+ 1 2 O ₂( ~g ) SO ₃( ~g )+y kcal aligned The heat of formation of SO ₂( ~g ) is given by :
Options
- Ax+y kcal
- By-2 x kcal
- C2 x y kcal
- D2 x+y kcal
Correct answer
B. y-2 x kcal
Step-by-step solution
(i) S ( g )+ 3 2 O ₂( ~g ) SO ₃( ~g )+2 x kcal H ₁ (ii) SO ₂( ~g )+ 1 2 O ₂( ~g ) SO ₃( ~g )+y kcal H ₂ (i) - (ii) aligned & S ( ~g )+ O ₂( ~g ) SO ₂( ~g ) H & H = H ₁- H ₂ & =-2 x-(-y)=(y-2 x) kcal aligned