Consider the seven following molecules and answer the questions below.

$C_6{H}_{5}F$

$C_6{H}_4{F}_2(3$ isomers$)$

$C_6{H}_3{F}_3(3$ isomers$)$

If one fluorine atom in each molecule is substituted by a chlorine atom, sketch the four

new molecules that have $C_{2v}$ point symmetry. State how many of the remaining $($non$-$

$C_{2v})$ chlorine$-$containing molecules have $C_s$ point symmetry.