Question

Identify the invalid equation.

Options

• ΔH = `∑"H"_"products" - ∑"H"_"reactants"`

• ΔH = ΔU + pΔV

• `Δ"H"_"(reaction)"^circ = sum "H"_"(product bonds)"^circ - sum "H"_"(reactant bonds)"^circ`

• ΔH = ΔU + ΔnRT

Answer 1

`Δ"H"_"(reaction)"^circ = sum "H"_"(product bonds)"^circ - sum "H"_"(reactant bonds)"^circ`

Explanation:

Relation between heat of reaction (ΔHr°) and bond enthalpies of reactants and products is

`Delta"H"_"r" = sum"BE"_"reactants" - sum"BE"_"products"`

`:. Δ"H"_"(reaction)"^circ = sum "H"_"(product bonds)"^circ - sum "H"_"(reactant bonds)"^circ`