What is the basic difference between enthalpy of formation and enthalp

1.	What is the basic difference between enthalpy of formation and enthalpy of reaction? Illustrate with suitable examples.
Answer» Enthalpy of formation is defined as enthalpy change when 1 mole of the substance is formed from the constituting elements in their standard states e.g. H₂(g) + 1/2O₂(g) → H₂O(l); Δ_fH = -286 kJ/mol Enthalpy of reactions is defined as enthalpy change when reactants react completely to form products according to balanced chemical reaction, e.g. N₂(g) + 3H₂(g) → 2NH₃(g) ΔH = -92.0 kJ

What is the basic difference between enthalpy of formation and enthalpy of reaction? Illustrate with suitable examples.

Answer»

Enthalpy of formation is defined as enthalpy change when 1 mole of the substance is formed from the constituting elements in their standard states e.g.

H₂(g) + 1/2O₂(g) → H₂O(l); Δ_fH = -286 kJ/mol

Enthalpy of reactions is defined as enthalpy change when reactants react completely to form products according to balanced chemical reaction,

e.g. N₂(g) + 3H₂(g) → 2NH₃(g)

ΔH = -92.0 kJ

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What is the basic difference between enthalpy of formation and enthalpy of reaction? Illustrate with suitable examples.

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