91Ó°ÊÓ

Which would have the larger lattice energy \(-\mathrm{CrCl}_{2}\) or \(\mathrm{CrCl}_{3}\) -assuming similar arrangements of ions in the lattice? Explain your answer.

In what types of compounds are resonance structures particularly common?

Which cation in each pair would be expected to form a chloride salt with the larger lattice energy, assuming similar arrangements of ions in the lattice? Explain your reasoning. a. \(\mathrm{Na}^{+}, \mathrm{Mg}^{2+}\) b. \(\mathrm{Li}^{+}, \mathrm{Cs}^{+}\) c. \(\mathrm{Cu}^{+}, \mathrm{Cu}^{2+}\)

Calculate the percent ionic character of \(\mathrm{PbS}\) and \(\mathrm{PbO}\) in the gas phase, given the following information: for \(\mathrm{PbS}, r=228.69 \mathrm{pm}\) and \(\mu=3.59 \mathrm{D}\); for \(\mathrm{PbO}, r=192.18 \mathrm{pm}\) and \(\mu=4.64 \mathrm{D}\). Would you classify these compounds as having covalent or polar covalent bonds in the solid state?

Which cation in each pair would be expected to form an oxide with the higher melting point, assuming similar arrangements of ions in the lattice? Explain your reasoning. a. \(\mathrm{Mg}^{2+}, \mathrm{Sr}^{2+}\) b. \(\mathrm{Cs}^{+}, \mathrm{Ba}^{2+}\) c. \(\mathrm{Fe}^{2+}, \mathrm{Fe}^{3+}\)

How can a thermochemical cycle be used to determine lattice energies? Which steps in such a cycle require an input of energy?

Although \(\mathrm{NaOH}\) and \(\mathrm{CH}_{3} \mathrm{OH}\) have similar formulas and molecular masses, the compounds have radically different properties. One has a high melting point, and the other is a liquid at room temperature. Which compound is which and why?