Question

Give the oxidation number of bromine in the following

$$\begin{gathered} \left(a\right)\mathit{K}\mathit{B}\mathit{r} \\ \left(b\right)\mathit{B}\mathit{r}{\mathit{F}}_{\mathbf{3}} \\ \left(c\right)\mathit{H}\mathit{B}\mathit{r}{\mathit{O}}_{\mathbf{3}}^{} \\ \left(d\right)\mathit{C}\mathit{B}{\mathit{r}}_{\mathbf{4}} \end{gathered}$$

Short answer

Answer:You need to provide the oxidation no of bromine for the given compounds.

Step-by-step solution

Oxidation state of bromine in KBr

Oxidation state of potassium is +1.

Let, oxidation state of bromine in KBr is x.

No you can write,

$$\begin{gathered} \left(+1\right)+x=0 \\ x=-1 \end{gathered}$$

Hence, oxidation state of bromine in KBr is -1.

Oxidation state of bromine in BrF3 

Oxidation state of Flurine is -1.

Let, oxidation state of bromine in BrF₃ is y.

No you can write,

$$\begin{gathered} y+3\left(-1\right)=0 \\ y=+3 \end{gathered}$$

Hence, oxidation state of bromine in BrF₃ is +3.

Oxidation state of bromine in HBrO3 

Oxidation state of Hydrogen is +1.

Oxidation state of Oxygen is -2.

Let, oxidation state of Bromine in HBrO₃is z.

No you can write,

$$\begin{gathered} \left(+1\right)+z+3\left(-2\right)=0 \\ z=+5 \end{gathered}$$

Hence, oxidation state of Bromine in HBrO₃ is +5

Oxidation state of bromine in CBr4 

Oxidation state of Carbon is +4.

Let, oxidation state of bromine in CBr₄is k.

No you can write,

$$\begin{gathered} \left(+4\right)+4\left(k\right)=0 \\ 4k=-4 \\ k=-1 \end{gathered}$$

Hence, oxidation state of bromine in CBr₄is -1.