Which of the following equations represents a reaction that provides the enthalpy of formation of `CH_(3)Cl`?

Options

A. `C(s)+HCl(g)+H_(2)(g)rarrCH_(3)Cl(g)`
B. `C(s)+3H(g)+Cl(g)rarrCH_(3)Cl(g)`
C. `C(s)+3//2H_(2)(g)+1//2Cl_(2)(g)rarrCH_(3)Cl(g)`
D. `CH_(4)(g)+Cl_(2)(g)rarrCH_(3)Cl(g)+HCl(g)`

Explanation

To determine which equation represents a reaction that provides the enthalpy of formation of CH₃Cl, we need to understand the concept of enthalpy of formation.

### Step-by-Step Solution:

1. **Identify the Elements in CH₃Cl**:
- The compound CH₃Cl consists of three elements: carbon (C), hydrogen (H), and chlorine (Cl).

2. **Write the Standard States of the Elements**:
- The standard state of carbon is solid carbon (C(s)).
- The standard state of hydrogen is diatomic hydrogen gas (H₂(g)).
- The standard state of chlorine is diatomic chlorine gas (Cl₂(g)).

3. **Formulate the Reaction**:
- The enthalpy of formation reaction for CH₃Cl can be represented as:
\[ C(s) + \frac{3}{2} H_2(g) + \frac{1}{2} Cl_2(g) \rightarrow CH_3Cl(g) \]
- Here, we take one mole of solid carbon, one and a half moles of hydrogen gas, and half a mole of chlorine gas to form one mole of CH₃Cl gas.

4. **Check the Given Options**:
- Review the provided equations to see which one matches the formulated reaction.
- The correct equation should include the elemental forms of C, H, and Cl, leading to the formation of CH₃Cl.

5. **Select the Correct Equation**:
- After reviewing the options, the equation that matches our derived reaction is the one that includes C(s), H₂(g), and Cl₂(g) leading to CH₃Cl(g).

### Conclusion:
The correct equation that represents the enthalpy of formation of CH₃Cl is:
\[ C(s) + \frac{3}{2} H_2(g) + \frac{1}{2} Cl_2(g) \rightarrow CH_3Cl(g) \]