The enthalpy of solution of sodium chloride is 4 kJ mol-1 and its enthalpy of hydration of ions is -784 kJ mol-1. What will be the lattice enthalpy of sodium chloride?

Question

The enthalpy of solution of sodium chloride is 4 kJ mol-1 and its enthalpy of hydration of ions is -784 kJ mol-1. What will be the lattice enthalpy of sodium chloride? (A) +780 kJ mol-1 (B) +394 kJ mol-1 (C) +788 kJ mol-1 (D) +398 kJ mol-1

Tardigrade Admin · Accepted Answer

Δ Hsol = Δ Hlattice+Δ Hhyd 4 = Δ Hlattice + (-784) Δ Hlattice = 4-(-784) = + 788 kJ mol-1

Q. The enthalpy of solution of sodium chloride is $4 k J m o l^{- 1}$ and its enthalpy of hydration of ions is $- 784 k J m o l^{- 1}$ . What will be the lattice enthalpy of sodium chloride?

$+ 780 k J m o l^{- 1}$

$+ 394 k J m o l^{- 1}$

$+ 788 k J m o l^{- 1}$

$+ 398 k J m o l^{- 1}$

$Δ H_{so l} = Δ H_{l a tt i ce} + Δ H_{h y d}$
$4 = Δ H_{l a tt i ce} + (- 784)$
$Δ H_{l a tt i ce} = 4 - (- 784)$
$= + 788 k J m o l^{- 1}$

Q. The enthalpy of solution of sodium chloride is 4kJmol−1 and its enthalpy of hydration of ions is −784kJmol−1. What will be the lattice enthalpy of sodium chloride?

+780kJmol−1

+394kJmol−1

+788kJmol−1

+398kJmol−1