$50 \mathrm{g}$ of ${\mathrm{CaCO}}_3$ is allowed to react with $73.5 \mathrm{g}$ of ${\mathrm{H}}_3{\mathrm{PO}}_4$. Calculate the following in moles:
($\mathrm{i}$) Amount of ${\mathrm{Ca}}_3{\left({\mathrm{PO}}_4\right)}_2$ formed
($\mathrm{ii}$) Amount of unreacted reagent

${\mathrm{KCIO}}_3$ decomposes by two parallel reactions,

($i$) $2{\mathrm{KClO}}_3\stackrel{\Delta }{⟶}2\mathrm{KCl}+3{\mathrm{O}}_2$  ($ii$) $4{\mathrm{KClO}}_3\stackrel{\Delta }{⟶}3{\mathrm{KClO}}_4+\mathrm{KCl}$

If $3$ moles of ${\mathrm{O}}_2$ and$1\mathrm{mol}$ of ${\mathrm{KClO}}_4$ is produced along with other products, then determine the initial moles of ${\mathrm{KClO}}_3$.