Problem 18
In terms of the potential energy change, why doesn't ionic bonding occur when two nonmetals react with each other?
Problem 19
When acetonitrile, \(\mathrm{CH}_{3}-\mathrm{C} \equiv \mathrm{N}:\), a molecular compound, is evaporated what type of particle is in the gas phase? How does this compare to the salt sodium chloride?
Problem 20
Describe what happens to the electron density around two hydrogen atoms as they come together to form an \(\mathrm{H}_{2}\). What happens to the energy of two hydrogen atoms as they approach each other? What happens to the spins of the electrons?
Problem 22
What factors control the bond length in a covalent bond?
Problem 23
How many covalent bonds are normally formed by (a) hydrogen, (b) carbon, (c) oxygen, (d) nitrogen, and (e) chlorine?
Problem 24
What is a polar covalent bond?
Problem 25
Define dipole moment in the form of an equation. What is the value of the debye (with appropriate units)?
Problem 26
Define electronegativity. On what basis did Pauling develop his scale of electronegativities?
Problem 27
Which element has the highest electronegativity? Which is the second most electronegative element? What are the horizontal and vertical periodic trends associated with electronegativity?
Problem 28
Among the following bonds, which are more ionic than covalent? (a) \(\mathrm{Si}-\mathrm{O}\) (b) \(\mathrm{Ba}-\mathrm{O}\) (c) \(\mathrm{Se}-\mathrm{Cl}\) (d) \(\mathrm{K}-\mathrm{Br}\)
