17
Thermodynamics
, Key Definitions Standard Molar Enthalpy of Formatio
the enthalpy change when one mole
First Ionisation Energy (ΔiHσ): the compound is formed from its elemen
standard enthalpy change when one standard conditions, all reactants an
mole of gaseous atoms is converted products in their standard states
into one mole of gaseous ions e.g., Na(s) + ½ Cl2(g)→ NaCl
through the removal of one mole of ΔfHσ = -411.2kJmol-1
electrons, each with a single positive
charge
e.g., Mg(s) → Mg+(g) + e-
ΔiHσ =+738kJmol-1 Second Electron Affinity (ΔeaHσ): the
*Continues for other IE* enthalpy change when a mole of
electrons is added to a mole of
gaseous ions each with a single
First Electron Affinity (ΔeaHσ): negative charge to form ions each
the standard enthalpy change with two negative charges
when a mole of gaseous atoms e.g., O-(g) + e- → O2-(g)
is converted to a mole of ΔeaHσ: +798kJmol-1
gaseous ions, each with a single
negative charge
e.g., O(g) + e- → O-(g)
ΔeaHσ = -141.1kJmol-1
Thermodynamics
, Key Definitions Standard Molar Enthalpy of Formatio
the enthalpy change when one mole
First Ionisation Energy (ΔiHσ): the compound is formed from its elemen
standard enthalpy change when one standard conditions, all reactants an
mole of gaseous atoms is converted products in their standard states
into one mole of gaseous ions e.g., Na(s) + ½ Cl2(g)→ NaCl
through the removal of one mole of ΔfHσ = -411.2kJmol-1
electrons, each with a single positive
charge
e.g., Mg(s) → Mg+(g) + e-
ΔiHσ =+738kJmol-1 Second Electron Affinity (ΔeaHσ): the
*Continues for other IE* enthalpy change when a mole of
electrons is added to a mole of
gaseous ions each with a single
First Electron Affinity (ΔeaHσ): negative charge to form ions each
the standard enthalpy change with two negative charges
when a mole of gaseous atoms e.g., O-(g) + e- → O2-(g)
is converted to a mole of ΔeaHσ: +798kJmol-1
gaseous ions, each with a single
negative charge
e.g., O(g) + e- → O-(g)
ΔeaHσ = -141.1kJmol-1
