The following reaction is an example of
`C_3H_8+Cl2overset(light)rarrC_3H_6Cl_2+2HCl`

Options

A. an addition reaction
B. a substitution reaction
C. an oxidation reaction
D. a reduction reaction

Answer

To determine the type of reaction represented by the equation:

\[ \text{C}_3\text{H}_8 + \text{Cl}_2 \overset{\text{light}}{\rightarrow} \text{C}_3\text{H}_6\text{Cl}_2 + 2\text{HCl} \]

we can analyze the reaction step by step.

### Step 1: Identify the Reactants and Products
The reactants are propane (\( \text{C}_3\text{H}_8 \)) and chlorine gas (\( \text{Cl}_2 \)). The products are 1,2-dichloropropane (\( \text{C}_3\text{H}_6\text{Cl}_2 \)) and hydrochloric acid (\( \text{HCl} \)).

### Step 2: Analyze the Structure of the Reactants
Propane is an alkane, which follows the general formula \( \text{C}_n\text{H}_{2n+2} \). For \( n = 3 \), we have \( \text{C}_3\text{H}_8 \). The chlorine gas is diatomic.

### Step 3: Understand the Reaction Mechanism
In this reaction, chlorine atoms are substituting hydrogen atoms in propane. Specifically, two hydrogen atoms are replaced by two chlorine atoms, resulting in the formation of 1,2-dichloropropane and hydrochloric acid.

### Step 4: Classify the Reaction
This reaction is classified as a **substitution reaction** because one or more hydrogen atoms in propane are replaced by chlorine atoms. Additionally, it involves the oxidation of chlorine from an oxidation state of 0 in \( \text{Cl}_2 \) to -1 in \( \text{HCl} \), indicating that reduction is also occurring.

### Step 5: Conclusion
Thus, the reaction is an example of a **substitution reaction** where chlorine is replacing hydrogen in the alkane, and it also involves oxidation-reduction processes.

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