For the reaction `CO_((g))+Cl_(2(g))hArrCOCl_(2(g))` the value
of `Delta n` is equal to :-

Answer

To find the value of Δn for the reaction:

\[ \text{CO}_{(g)} + \text{Cl}_{2(g)} \rightleftharpoons \text{COCl}_{2(g)} \]

we will follow these steps:

### Step 1: Identify the reactants and products
In the given reaction, we have:
- **Reactants**: CO (g) and Cl2 (g)
- **Product**: COCl2 (g)

### Step 2: Count the number of moles of reactants and products
- **Number of moles of reactants**:
- CO: 1 mole
- Cl2: 1 mole
- Total moles of reactants = 1 + 1 = 2 moles

- **Number of moles of products**:
- COCl2: 1 mole
- Total moles of products = 1 mole

### Step 3: Calculate Δn
Δn is defined as the difference between the number of moles of products and the number of moles of reactants:

\[ \Delta n = \text{(Number of moles of products)} - \text{(Number of moles of reactants)} \]

Substituting the values we found:

\[ \Delta n = 1 - 2 = -1 \]

### Final Answer
Thus, the value of Δn for the reaction is:

\[ \Delta n = -1 \]

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