Statement (A): A balanced chemical equation tells us about the total number of atoms of each element on reactant side and product side. 

Statement (B): In a chemical equation if the number of atoms of each kind are not equal on both sides, such a chemical equation is a skeletal chemical equation. 

Statement (C): Chemical equations are balanced by F number method

I. Example ${\mathrm{H}}_{2\left(\mathrm{g}\right)}+{\mathrm{Cl}}_{2\left(\mathrm{g}\right)}\to 2{\mathrm{HCl}}_{\left(\mathrm{g}\right)}$ here number of hydrogen atoms on reactants side and product side is two, number of chlorine atoms on reactant side and product side is two.

II. Example ${\mathrm{H}}_{2\left(\mathrm{g}\right)}+{\mathrm{Cl}}_{2\left(\mathrm{g}\right)}\to {\mathrm{HCl}}_{\left(\mathrm{g}\right)}$it is a Skeletal chemical equation

 III. The frequency of occurrence of various elements in an equation is called F-Number. Ex: $2{\mathrm{KNO}}_3\to 2{\mathrm{KNO}}_2+{\mathrm{O}}_2$

Potassium atom is present at one place in the reactants and one place in the products. Thus its frequency in the whole equation is 2.