The ionization energy for potassium is 419 kJ/mol. The electron affinity for bromine is -325 kJ/mol. Use these values and Hess's law to calculate the change in enthalpy for the following reaction per mole of reagent: K(g)+Br(g)→K+(g)+Br−(g), ΔH=?

Respuesta :

Answer:

ΔH= 94 kJ/mol

Explanation:

K (g) → K⁺ (g) + e⁻  ΔH= 419 kJ/mol

Br (g) + e⁻ → Br⁻ (g) ΔH= -325 kJ/mol

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K (g) + Br (g) → K⁺ (g) + Br⁻ (g)   ΔH=419 + (-325)

ΔH= 94 kJ/mol

The Hess' Law states that the enthalphy values of steps of a mechanism can be used to calculate the change in enthalpy of a global reaction.