Assertion : For the reaction
`CHCI_(3) + CI_(2) to CCI_(4) HCI`
Rate = `k[CHCI_(3)][CI_(2)]^(1//2)`
Reason : Rate of reaction is always equals to the sum of the stoichiometic coefficients of the reacting species in a balanced chemical equation.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Analyze the Assertion
The assertion states that for the reaction:
\[ \text{CHCl}_3 + \text{Cl}_2 \rightarrow \text{CCl}_4 + \text{HCl} \]
the rate of reaction is given by:
\[ \text{Rate} = k[\text{CHCl}_3][\text{Cl}_2]^{1/2} \]

This indicates that the rate of reaction depends on the concentration of CHCl3 raised to the first power and the concentration of Cl2 raised to the half power. This form of rate law suggests that the reaction is not elementary and that the rate law must be determined experimentally.

### Step 2: Analyze the Reason
The reason states that the rate of reaction is always equal to the sum of the stoichiometric coefficients of the reacting species in a balanced chemical equation. This statement is incorrect. The rate of a reaction is determined by the rate law, which may or may not correspond to the stoichiometric coefficients of the balanced equation. The rate law can depend on various factors, including the mechanism of the reaction.

### Step 3: Conclusion
From the analysis:
- The assertion is correct because it accurately describes the rate law for the reaction.
- The reason is false because it incorrectly states a general rule about reaction rates that does not hold true.

Thus, the correct answer is that the assertion is true, but the reason is false.

### Final Answer
The assertion is true, and the reason is false.