INO-24

Born–Haber lattice snapshot

U = ΔHsub + IE + ½ D + EA + ΔHf (signs as written for MX).

Reading speed

LatticeBorn–Haber

Governing equation

U=\Delta H_{f}-\bigl(\Delta H_{sub}+IE+\tfrac12 D+EA\bigr)

where

\Delta H_f: Formation enthalpy (kJ/mol)
\Delta H_{sub}: Sublimation (kJ/mol)
IE: Ionisation energy (kJ/mol)
D: X–X bond energy (kJ/mol)
EA: Electron affinity (X) (kJ/mol)
U: Lattice energy (kJ/mol)

Lecture brief

Historical brief

Pauling and Allred–Rochow electronegativity, Kapustinskii lattice energy, CFSE and Goldschmidt radii organise the periodic solid. The sheets predict bond character and crystal packing. This sheet (INO-24 — Born–Haber lattice snapshot) is the form associated with Born–Haber. Working symbols: $\Delta H_f$ , $\Delta H_{sub}$ , $IE$ , $D$ , $EA$ $\rightarrow$ $U$ . Hess's law around the formation of a crystal from the elements, isolating the lattice step.

Purpose

Purpose: compute

U

from

\Delta H_f

\Delta H_{sub}

IE

D

EA

in Inorganic chemistry via

U=\Delta H_{f}-\bigl(\Delta H_{sub}+IE+\tfrac12 D+EA\bigr)

U = ΔHsub + IE + ½ D + EA + ΔHf (signs as written for MX). Use it when a real inorganic chemistry question must be answered in SI before a code check.

Live realistic example

In symbols

Live case. Given

\Delta H_f = -411.000\,\mathrm{kJ/mol}

\Delta H_{sub} = 107.000\,\mathrm{kJ/mol}

IE = 496.000\,\mathrm{kJ/mol}

D = 242.000\,\mathrm{kJ/mol}

EA = -349.000\,\mathrm{kJ/mol}

, the governing relation

U=\Delta H_{f}-\bigl(\Delta H_{sub}+IE+\tfrac12 D+EA\bigr)

yields

U = -786.0\,\mathrm{kJ/mol}

. MX from M(s) + ½ X2. Enter tabulated steps in kJ/mol. Move a slider: the numbers are this situation, not a canned story.

Calculator

Inputs

Formation enthalpy \Delta H_f-411 kJ/molSublimation \Delta H_{sub}107 kJ/molIonisation energy IE496 kJ/molX–X bond energy D242 kJ/molElectron affinity (X) EA-349 kJ/mol

Outputs

Lattice energy U-786.0 kJ/mol

Reading speed

Watch on YouTube

Free library

Full library

Free PDF / open book

YouTube channels

00:0 / 00:08

Narration of this film

MX from M(s) + ½ X2. Enter tabulated steps in kJ/mol.

Hess's law around the formation of a crystal from the elements, isolating the lattice step.

Reading speed

Watch on YouTube