The order of the reaction
`5" Br"^(-)(aq)+BrO_(3)^(-)(aq)+6" H"^(+)(aq)to3" Br"_(2)(aq)+7" H"_(2)O(l)` is

Explanation

To determine the order of the reaction:

\[ 5 \text{Br}^-(aq) + \text{BrO}_3^-(aq) + 6 \text{H}^+(aq) \rightarrow 3 \text{Br}_2(aq) + 7 \text{H}_2O(l) \]

we will follow these steps:

### Step 1: Identify the Reactants
The reactants in the given reaction are:
- \( \text{Br}^- \)
- \( \text{BrO}_3^- \)
- \( \text{H}^+ \)

### Step 2: Determine the Stoichiometric Coefficients
The stoichiometric coefficients of the reactants are:
- For \( \text{Br}^- \): 5
- For \( \text{BrO}_3^- \): 1
- For \( \text{H}^+ \): 6

### Step 3: Define the Order of Reaction
The order of a reaction is defined as the sum of the powers of the concentration terms in the rate law. For a single-step reaction, the order can be directly related to the stoichiometric coefficients of the reactants.

### Step 4: Calculate the Total Order
Now, we will sum the stoichiometric coefficients of the reactants:
- Order from \( \text{Br}^- \): 5
- Order from \( \text{BrO}_3^- \): 1
- Order from \( \text{H}^+ \): 6

Thus, the total order of the reaction is:
\[ 5 + 1 + 6 = 12 \]

### Conclusion
The order of the reaction is **12**.

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