In order to determine ∆Hlatt of ionic compound, which one is correct relationship?
Correct answer: A. ΔΗlatt = ΔΗf- ΔΗx
- A. ΔΗlatt = ΔΗf- ΔΗx
- B. ΔΗlatt = ΔΗf + ΔΗx
- C. ΔΗlatt = ΔΗa + ΔΗv
- D. ΔΗlatt = ΔΗf - ΔΗsol
Explanation
Option A is correct.The correct relationship to determine the lattice energy of an ionic compound is:ΔHlatt =ΔHf − ΔHx ΔHf is the heat of formation of the ionic compound. ΔHx is the heat of sublimation of the metal. The lattice energy is the energy required to convert the gaseous ions of the ionic compound into the solid ionic compound. The heat of formation of the ionic compound is the heat released when the ionic compound is formed from its constituent elements in their standard states. The heat of sublimation of the metal is the heat required to convert the metal from its solid state to its gaseous state.
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