• question_answer Determine the oxidation number of the element in the bold in the following species (i)$Si{{H}_{4}}$                (ii)$B{{H}_{3}}$                               (iii)$B{{F}_{3}}$                (iv)${{S}_{2}}O{{_{3}^{{}}}^{2-}}$           (v)$BrO{{_{4}^{{}}}^{-}}$     (vi)$HP{{O}_{4}}^{2-}$

 (i) $Si{{H}_{4}}$ : $\overset{x}{\mathop{S}}\,i{{\overset{+1}{\mathop{H}}\,}_{4}}$ $x+4(+1)=0$ or$x=-4$ (ii) $B{{H}_{3}}$ $:\overset{x}{\mathop{B}}\,{{\overset{+1}{\mathop{H}}\,}_{3}}$ $x+3(+1)=0$ or $x=-3$ (iii) $B{{F}_{3}}$ :$\overset{x}{\mathop{B}}\,{{\overset{-1}{\mathop{F}}\,}_{3}}$ $x+3(-1)=0$ or $x=+3$ (iv) ${{S}_{2}}{{O}_{3}}^{2-}$ $:{{\overset{x}{\mathop{S}}\,}_{2}}{{\overset{-2}{\mathop{O}}\,}_{3}}$ $2(x)+3(-2)=-2$ or $x=+2$ (v) $BrO{{_{4}^{{}}}^{-}}$ $:\overset{x}{\mathop{B}}\,r\,{{\overset{-2}{\mathop{O}}\,}_{4}}$ $x+4(-2)=-1$ or $x=+7$ (vi) $HP{{O}_{4}}^{2-}$ : $\overset{+1}{\mathop{H}}\,\overset{x}{\mathop{P}}\,\,{{\overset{-2}{\mathop{O}}\,}_{4}}$ $(+1)+x+4(-2)=-2$ or $x=+5$