Problem 1
With reference to the oxygen atom, explain what you understand by the (a) first ionization energy, (b) second ionization energy, (c) first electron affinity, (d) second electron affinity and (e) enthalpy change associated with the attachment of an electron.
Problem 2
The first five ionization energies of a gaseous atom \(X\) are 589,1148,4911,6494 and \(8153 \mathrm{kJ} \mathrm{mol}^{-1},\) To what group is this element likely to belong?
Problem 3
The first ionization energies of oxygen \((Z=8)\) fluorine \((Z=9),\) neon \((Z=10)\) and sodium \((Z=11)\) are 1312,1681,2080 and \(495 \mathrm{kJ} \mathrm{mol}^{-1}\) respectively. Rationalize the trend in these values in terms of the electronic structures of these elements.
Problem 4
Calculate the enthalpy change that accompanies the process: \\[ \frac{1}{2} \mathrm{Li}_{2}(\mathrm{g})-\mathrm{Li}^{+}(\mathrm{g})+\mathrm{e}^{-} \\] given that the bond enthalpy for dilithium is \(110 \mathrm{kJ} \mathrm{mol}^{-1}\) and \(I E_{1}\) for lithium is \(520 \mathrm{kJ} \mathrm{mol}^{-1}\)
Problem 5
Calculate the enthalpy change that accompanies the reaction: \\[ \frac{1}{2} \mathrm{Li}_{2}(\mathrm{g})+\mathrm{e}^{-}-\mathrm{Li}^{-}(\mathrm{g}) \\] given that the bond enthalpy for \(L_{i}\), is \(110 \mathrm{kJ} \mathrm{mol}^{-1}\) and \(E A_{1}\) for lithium is \(60 \mathrm{kJ} \mathrm{mol}^{-1}\)
Problem 11
Uranium(IV) oxide adopts a fluorite structure. From this structure, show that the formula of the oxide is \(\mathrm{UO}_{2}\)
Problem 15
(a) Gallium phosphide is used is solar energy conversion, and it crystallizes with the zinc blende lattice. What is the formula of gallium phosphide? Rationalize this formula in terms of the positions of Ga and \(P\) in the periodic table. (b) Crystalline cerium(IV) oxide contains 4-coordinate \(\mathrm{O}^{2-}\) ions. What is the coordination number of the Ce(IV) centres? The oxide adopts one of the lattices described in Chapter \(8 .\) Suggest which lattice it is.
Problem 16
A bromide of indium, \(\operatorname{In} \mathrm{Br}_{x},\) adopts the NaCl lattice but only one-third of the metal ion sites are occupied. What is the oxidation state of indium in this compound?
Problem 20
KF crystallizes with an NaCl structure, and the internuclear separation is \(266 \mathrm{pm}\). The density of \(\mathrm{KF}\) is \(2.48 \mathrm{gcm}^{-3} .\) Estimate a value for the Avogadro constant.
Problem 27
(a) Draw a Lewis structure for the cyanide ion. (b) Comment on the fact that sodium cyanide, \(\mathrm{NaCN},\) crystallizes with an \(\mathrm{NaCl}\) structure.
