The given elementary reaction `2FeCl_3+SnCl_2rarr2FeCl_2+SnCl_4` is an example of

Options

A. Third order reaction
B. First order reaction
C. Second order reaction
D. None of these

Answer

To determine the order of the given elementary reaction \(2 \text{FeCl}_3 + \text{SnCl}_2 \rightarrow 2 \text{FeCl}_2 + \text{SnCl}_4\), we can follow these steps:

### Step 1: Identify the Stoichiometric Coefficients
In the reaction, we have:
- \(2\) moles of \(\text{FeCl}_3\)
- \(1\) mole of \(\text{SnCl}_2\)

### Step 2: Write the Rate Law Expression
For an elementary reaction, the rate law can be expressed based on the stoichiometric coefficients of the reactants:
\[ \text{Rate} = k [\text{FeCl}_3]^2 [\text{SnCl}_2]^1 \]
where \(k\) is the rate constant.

### Step 3: Determine the Order of the Reaction
The order of the reaction is the sum of the powers of the concentration terms in the rate law:
- The order with respect to \(\text{FeCl}_3\) is \(2\).
- The order with respect to \(\text{SnCl}_2\) is \(1\).

Thus, the total order of the reaction is:
\[ \text{Total Order} = 2 + 1 = 3 \]

### Step 4: Conclusion
Since the total order of the reaction is \(3\), we conclude that the reaction is a **third order reaction**.

### Final Answer
The given elementary reaction \(2 \text{FeCl}_3 + \text{SnCl}_2 \rightarrow 2 \text{FeCl}_2 + \text{SnCl}_4\) is an example of a **third order reaction**.

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