Question

The values of heat of formation of SO₂ and SO₃
are –298.2 kJ and –98.2 kJ. The heat of formation
of the reaction SO₂ + (1/ 2)O₂ ➝SO ₃ will be
(a) –200 kJ (b) –356.2 kJ
(c) + 200 kJ (d) – 396.2 kJ

Answer 1

Answer:

sorry it is tough as I'm in junior class

Answer 2

The heat of formation  of the reaction is (a) –200 kJ

Explanation:

The heat of formation  of the reaction is given by the formula:

Heat formation = Heat formation of reactant - Heat formation of product

The chemical reaction given in the question is:

SO₂ + (1/2)O₂ ➝ SO₃

Heat formation = Heat formation of SO₂ - Heat formation of SO₃

On substituting the values, we get,

ΔH° = - 298.2 - (- 98.2)

ΔH° = - 298.2 + 98.2

∴ ΔH° = - 200 kJ