Calculate the equivalent weight of chlorine in the reaction of Chlorine with NaOH

Answer

To calculate the equivalent weight of chlorine in the reaction with sodium hydroxide (NaOH), we will follow these steps:

### Step 1: Write the balanced chemical equation
The reaction between chlorine (Cl₂) and sodium hydroxide (NaOH) can be represented as follows:

\[ \text{NaOH} + \text{Cl}_2 \rightarrow \text{NaCl} + \text{NaClO}_3 + \text{H}_2\text{O} \]

Balancing this equation gives:

\[ 6 \text{NaOH} + 3 \text{Cl}_2 \rightarrow 5 \text{NaCl} + \text{NaClO}_3 + 3 \text{H}_2\text{O} \]

### Step 2: Determine the oxidation states of chlorine
In this reaction, chlorine undergoes two changes in oxidation states:
1. From Cl₂ (0 oxidation state) to Cl⁻ (−1 oxidation state) in NaCl.
2. From Cl₂ (0 oxidation state) to ClO₃⁻ (+5 oxidation state) in NaClO₃.

### Step 3: Calculate the n-factor for each change
- For the formation of NaCl:
- Change in oxidation state: 0 to -1
- n-factor = 1 (since one electron is gained)

- For the formation of NaClO₃:
- Change in oxidation state: 0 to +5
- n-factor = 5 (since five electrons are lost)

### Step 4: Calculate the equivalent weight
The equivalent weight (EW) is calculated using the formula:

\[ \text{Equivalent Weight} = \frac{\text{Atomic Weight}}{\text{n-factor}} \]

For chlorine:
- Atomic weight of chlorine = 35.5 g/mol

Now, we calculate the equivalent weights for both changes:
1. For Cl⁻:
\[ \text{EW}_1 = \frac{35.5}{1} = 35.5 \text{ g/equiv} \]

2. For ClO₃⁻:
\[ \text{EW}_2 = \frac{35.5}{5} = 7.1 \text{ g/equiv} \]

### Step 5: Calculate the total equivalent weight
To find the total equivalent weight of chlorine in the reaction, we sum the equivalent weights from both changes:

\[ \text{Total Equivalent Weight} = \text{EW}_1 + \text{EW}_2 = 35.5 + 7.1 = 42.6 \text{ g/equiv} \]

### Final Answer
The equivalent weight of chlorine in the reaction with NaOH is **42.6 g/equiv**.

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