Question

Oxidation number of aluminium in $\text{N}{\text{a}}_{\text{3}}\text{Al}{\text{F}}_{\text{6}}$ is:

• A. 3
• B. 2
• C. -2
• D. 1

Answer 1

Answer: (A)

In $\text{N}{\text{a}}_{\text{3}}\text{Al}{\text{F}}_{\text{6}}$ $(+1\times 3)+x+(-1\times 6)=0$ $3+x-6=0$ $x=+3$ $\therefore$ Oxidation number of Al is $+3.$