$\begin{array}{1 1}\text{The stability of the +4 oxidation state of elements of Group 14 decreases down the group}\\\text{The stability of the +2 oxidation state of elements of Group 14 increases down the group}\\\text{Stannous fluoride is a covalent compound}\\\text{A majority of the compounds of elements of Group 14 are four covalent and involve }sp^3\text{ hybridization}\end{array} $
