Identify the correct statement (s) among the following.

a)  $3{\mathrm{Br}}_2+6\mathrm{NaOH}\to 5\mathrm{NaBr}+{\mathrm{NaBrO}}_3+3{\mathrm{H}}_2\mathrm{O}$
b) ${\mathrm{O}}_3+{\mathrm{SO}}_2\to {\mathrm{O}}_2+{\mathrm{SO}}_3$
d)  reacts with excess of NH₃ to produce ammonium chloride and nitrogen
$\begin{array}{l}2{\mathrm{NH}}_3+3{\mathrm{Cl}}_2\to {\mathrm{N}}_2+6\mathrm{HCl}\\ 6{\mathrm{NH}}_3+6\mathrm{HCl}\to 6{\mathrm{NH}}_4\mathrm{Cl}+6\mathrm{HCl}\\ \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\\ 8{\mathrm{NH}}_3+3{\mathrm{H}}_2\to {\mathrm{N}}_2+6{\mathrm{NH}}_4\mathrm{Cl}\end{array}$