The lattice energy of KBr is

CHEMISTRY · Single correct · A Level · Chemistry · Energetics · Energetics

Problem

+671\,\text{kJ mol}^{-1}

, and the sum of the hydration enthalpies of K⁺ and Br⁻ is

-676\,\text{kJ mol}^{-1}

. What is the approximate enthalpy change,

\Delta H_{\text{solution}}

, for dissolving 1.0 mol of KBr in a large volume of water? (a)

+5\,\text{kJ mol}^{-1}

(b)

+671\,\text{kJ mol}^{-1}

(c)

-5\,\text{kJ mol}^{-1}

(d)

-1.35\times10^{3}\,\text{kJ mol}^{-1}