Problem 1
Give the directions of the dipole moments in the (a) \(C-B r_{i}, (b) N-H\) following bonds: : (c) \(\mathrm{Cl}-\mathrm{F}\) (d) \(\mathrm{C}-\mathrm{S}\)
Problem 2
Which of the following molecules are polar? (a) \(\mathrm{CH}_{3} \mathrm{Cl}\) (b) \(\mathrm{CH}_{2} \mathrm{Cl}_{2} ;(\mathrm{c}) \mathrm{SO}_{3}:(\mathrm{d}) \mathrm{HCHO}\) (e) \(\mathrm{HBr}\) (f) \(\mathrm{H}_{2} \mathrm{O} ;(\mathrm{g}) \mathrm{CH}_{3} \mathrm{OH}\) (h) \(\mathrm{CBr}_{4}\)
Problem 4
Which of the following molecules are polar? (a) \(\mathrm{SO}_{2} ;(\mathrm{b}) \mathrm{CO}_{2} ;(\mathrm{c}) \mathrm{H}_{2} \mathrm{O}\) \(;(d) \mathrm{HC} \equiv \mathrm{CCl}\) (e) \(\mathrm{H}_{2} \mathrm{S}\)
Problem 6
The molecular dipole moments of the gas phase molecules \(\mathrm{CH}_{2} \mathrm{Br}_{2}, \mathrm{CClF}_{3}\) and \(\mathrm{HCN}\) are 1.43,0.50 and 2.98 D respectively, Draw the structure of each molecule and indicate the direction of the resultant dipole moment.
Problem 8
How might values of molecular dipole moments help you to distinguish between ( \(E\) )- and ( \(Z\) )-1,2 dibromoethene?
Problem 9
Explain what is meant by the inductive effect with reference to the compounds \(\mathrm{CF}_{3} \mathrm{CO}_{2} \mathrm{H}\) and \(\mathrm{CH}_{3} \mathrm{CO}_{2} \mathrm{H}\)
