Question

Assign oxidation numbers to the elements in the following ionic compounds.
a. $NaBr$ b. $MgO$ c. $Al{F}_3$

• A. a. Na = $+1$, Br = $-1$; b. Mg = $+2$, O = $-2$; c. Al = $+3$, F = $-1$
• B. a. Na = $+2$, Br = $-2$; b. Mg = $+2$, O = $-2$; c. Al = $+3$, F = $-1$
• C. a. Na= $+1$, Br = $-1$; b. Mg = $+1$, O = $-1$; c. Al = $+3$, F = $-1$
• D. None of these

Answer 1

The correct option is A a. Na = $+1$, Br = $-1$; b. Mg = $+2$, O = $-2$; c. Al = $+3$, F = $-1$

In sodium bromide ($NaBr$), the oxidation number of Na is $+1$ and that of Br is $-1$.
In magnesium oxide ($MgO$), the oxidation number of Mg is $+2$ and that of O is $-2$.
In Aluminium fluoride ($Al{F}_3$), the oxidation number of Al is $+3$ and that of F is $-1$.