Chapter 9

How much energy, in kilojoules, is required to remove all the third-shell electrons in a mole of gaseous silicon atoms?

Use ionization energies and electron affinities listed in the text to determine whether the following reaction is endothermic or exothermic. $$\mathrm{Mg}(\mathrm{g})+2\mathrm{F}(\mathrm{g})⟶{\mathrm{Mg}}^{2+}(\mathrm{g})+2{\mathrm{F}}^{-}(\mathrm{g})$$

The ${\mathrm{Na}}^{+}$ ion and the Ne atom are isoelectronic. The ease of loss of an electron by a gaseous Ne atom, $I_1$ has a value of $2081\mathrm{kJ}/\mathrm{mol}.$ The ease of loss of an electron from a gaseous ${\mathrm{Na}}^{+}$ ion, $I_2$, has a value of $4562\mathrm{kJ}/\mathrm{mol}.$ Why are these values not the same?

Compare the elements $\mathrm{Al},\mathrm{Si},\mathrm{S},$ and $\mathrm{Cl}.$ (a) Place the elements in order of increasing ionization energy. (b) Place the elements in order of increasing electron affinity.

Compare the elements $\mathrm{Na},\mathrm{Mg},\mathrm{O},$ and $\mathrm{P}.$ (a) Place the elements in order of increasing ionization energy. (b) Place the elements in order of increasing electron affinity.

Unpaired electrons are found in only one of the following species. Indicate which one, and explain why: ${\mathrm{F}}^{-},{\mathrm{Ca}}^{2+},{\mathrm{Fe}}^{2+},{\mathrm{S}}^{2-}$

Which of the following species has the greatest number of unpaired electrons (a) $\mathrm{Ge};$ (b) $\mathrm{Cl};$ (c) ${\mathrm{Cr}}^{3+}$ (d) Br -?

Which of the following species would you expect tobe diamagnetic and which paramagnetic? (a) ${\mathrm{K}}^{+}=$ (b) ${\mathrm{Cr}}^{3+};$ (c) ${\mathrm{Zn}}^{2+};$ (d) $\mathrm{Cd};$ (e) ${\mathrm{Co}}^{3+};$ (f) ${\mathrm{Sn}}^{2+};$ (g) Br.

Write electron configurations consistent with the following data on numbers of unpaired electrons: ${\mathrm{Ni}}^{2+},2;{\mathrm{Cu}}^{2+},1;{\mathrm{Cr}}^{3+},3.$

Must all atoms with an odd atomic number be paramagnetic? Must all atoms with an even atomic number be diamagnetic? Explain.