REVIEW QUESTIONS

Chapter 9

  1. Draw Lewis structures for each of the following structures and assign formal charges to each atom:
    a)
    b) ( N and O are bonded to one another)
    c)
  2. Draw two possible resonance structures for the isocyanate ion ( ) and using formal charges determine which structure has greater contribution to the resonance hybrid.
  3. Arrange the bonds in each of the following sets in order if increasing polarity:
    a)
    B-F

    b)

  4. Classify each of the following bonds as ionic, polar covalent or non-polar covalent:
    a)
    b)
    c)
    d)
  5. Use bond energies listed in Table 9.3 in your textbook to find for the reactions shown below:

    b)
  6. Use the data provided below to calculate the lattice energy of RbCl . Is this value greater or less than the lattice energy of NaCl? Explain.
  1. Arrange the following compounds in order of increasing lattice energy. Provide explanation for your choices.
NaF CaO CsI
8. Oxalic acid is a weak acid that can lose two hydrogens to form the following anions:
Draw Lewis structures for the two anions above, and comment on the relative strength and length of their bonds.
9. Bond energies can be combined with values for other atomic properties to obtain values that cannot be measured directly. Use bond energy and other data found in your textbook to calculate for the ionic dissociation of chlorine gas:
  1. Tetrazene is a thermally unstable nitrogen hydride with the atom sequence shown below. It decomposes above to form hydrazine and nitrogen gas. Draw a Lewis structure for tetrazene and calculate the for its decomposition.
  2. Thionyl chloride ( ) can have the 3 skeletal structures shown below. Complete the Lewis structure for each, assign formal charges and determine which structure is the most plausible for this compound.
Cl Cl S
Cl S O Cl O S Cl Cl O
  1. Rank the length of the bond length in the following ions:


  2. Two compounds are isomers if they have the same chemical formula but a different arrangement of atoms. Use bond energies available in Table 9.3 in your test to estimate for each of the following isomerization reactions and indicate which isomer is more stable.
    a)

    b)