In the reaction
`3Br_(2)+6CO_(3)^(2-)+3H_(2)Orarr5Br^(ө)+BrO_(3)^(ө)+6HCO_(3)^(ө)`

Options

A. Bromine is oxidised and carbonate is reduced
B. Bromide is reduced and water is oxidised
C. Bromine is neither reduced nor oxidised
D. Brominde is both reduced and oxidised

Explanation

To solve the given redox reaction, we need to analyze the oxidation states of the elements involved, particularly bromine and carbonate ions. Here’s a step-by-step breakdown of the solution:

### Step 1: Identify the Reactants and Products
The reaction is:
\[ 3Br_2 + 6CO_3^{2-} + 3H_2O \rightarrow 5Br^{-} + BrO_3^{-} + 6HCO_3^{-} \]

### Step 2: Determine the Oxidation States
- **Bromine in \( Br_2 \)**: The oxidation state of bromine in \( Br_2 \) is 0.
- **Bromine in \( Br^{-} \)**: The oxidation state of bromine in \( Br^{-} \) is -1.
- **Bromine in \( BrO_3^{-} \)**: To find the oxidation state of bromine in \( BrO_3^{-} \), we can use the formula:
\[ x + 3(-2) = -1 \implies x - 6 = -1 \implies x = +5 \]
So, the oxidation state of bromine in \( BrO_3^{-} \) is +5.

### Step 3: Analyze the Changes in Oxidation States
- **Reduction**: The oxidation state of bromine changes from 0 in \( Br_2 \) to -1 in \( Br^{-} \). This indicates that bromine is being reduced.
- **Oxidation**: The oxidation state of bromine changes from 0 in \( Br_2 \) to +5 in \( BrO_3^{-} \). This indicates that bromine is being oxidized.

### Step 4: Analyze the Carbonate Ion
- **Carbonate Ion \( CO_3^{2-} \)**: The oxidation state of carbon in \( CO_3^{2-} \) is +4 (calculated as follows: \( x + 3(-2) = -2 \implies x - 6 = -2 \implies x = +4 \)).
- In the products, the carbonate is converted to bicarbonate \( HCO_3^{-} \), where the oxidation state of carbon remains +4. Thus, there is no change in the oxidation state of carbon, indicating that the carbonate ion is neither oxidized nor reduced.

### Step 5: Conclusion on the Reaction
Since bromine undergoes both oxidation and reduction, we conclude that this reaction is a redox reaction where:
- Bromine is both reduced (to \( Br^{-} \)) and oxidized (to \( BrO_3^{-} \)).
- The carbonate ions do not undergo any change in oxidation state.

### Final Answer
The correct option is:
**D: Bromine is both reduced and oxidized.**