In the following halogenated organic compounds the one with maximum number of chlorine atoms in its…

Percentage of chlorine content = $\frac{\text{mass of chlorine}}{\text{mass of organic compound}}\mathrm{ }\times 100$ 

(A) Chloral $\left({\mathrm{CCl}}_3\mathrm{CHO}\right)$:

Percentage of chlorine content = $\frac{3 \times 35.5}{147.5} \times 100 = 72.203\%$

(B) Gammaxene $\left({\mathrm{C}}_6{\mathrm{H}}_6{\mathrm{Cl}}_6\right)$:

Percentage of chlorine content = $\frac{6 \times 35.5}{291} \times 100 = 73.2\%$

(C) Chloropicrin ${\mathrm{Cl}}_3\mathrm{C}–{\mathrm{NO}}_2$:

Percentage of chlorine content = $\frac{3 \times 35.5}{165} \times 100 = 64.54\%$

(D) Freon-$12$ $\left({\mathrm{CF}}_2{\mathrm{Cl}}_2\right)$:

Percentage of chlorine content = $\frac{2 \times 35.5}{121} \times 100 = 58.67\%$

As per the percentage of chlorine, Gammaxene has the maximum number of chlorine atoms.