Topic 4.1 Energetics II

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4.1a understand the definition of enthalpy of atomisation, DH^q_a  , enthalpy of hydration, DH^q_hyd and lattice enthalpy, DH^q_latt 
· lattice enthalpy to be expressed as the enthalpy change for the process 
M⁺(g) + X ^- (g)® M⁺X^- (s)

4.1b construct a Born-Haber cycle and carry out associated calculations
· not to be limited to sodium chloride

4.1c understand that values of lattice enthalpies calculated from the Born-Haber cycle may differ from those calculated from a purely ionic model

4.1d understand the factors that influence the value of the lattice enthalpy
· limited to the radius and charge of the ions

4.1e understand the part played by lattice enthalpy and enthalpy of hydration in rationalising the variation in solubilities of the hydroxides and the sulphates of Group 2.