`Cl + Cl to Cl_2`, this is an example for

Options

A. Endothermic reaction
B. Exothermic reaction
C. Either exothermic or endothermic
D. Neither exothermic nor endothermic

Explanation

To determine whether the reaction \( \text{Cl} + \text{Cl} \rightarrow \text{Cl}_2 \) is exothermic or endothermic, we can follow these steps:

### Step 1: Understand the Reaction
The reaction involves two chlorine atoms (Cl) combining to form a chlorine molecule (Cl2). Each chlorine atom has an unpaired electron.

**Hint:** Identify the reactants and products in the reaction.

### Step 2: Analyze Electron Configuration
The electron configuration of chlorine is \( 1s^2, 2s^2, 2p^6, 3s^2, 3p^5 \). The outermost shell has 7 electrons, meaning each chlorine atom has one unpaired electron that can participate in bonding.

**Hint:** Recall the concept of electron configuration and the significance of unpaired electrons in bonding.

### Step 3: Formation of Cl2
When two chlorine atoms come together, they share their unpaired electrons to form a covalent bond, resulting in a stable Cl2 molecule. This sharing of electrons allows both atoms to achieve a full octet, which is a stable electron configuration.

**Hint:** Consider how atoms achieve stability through bonding.

### Step 4: Energy Considerations
As the chlorine atoms come closer to form Cl2, their electrostatic energy decreases. This decrease in energy indicates that the system is becoming more stable.

**Hint:** Think about how energy changes during the formation of chemical bonds.

### Step 5: Determine the Type of Reaction
Since the formation of Cl2 from Cl atoms releases energy (in the form of heat), this reaction is classified as an exothermic reaction. The energy released corresponds to the difference in energy between the reactants (Cl atoms) and the product (Cl2 molecule).

**Hint:** Remember that in exothermic reactions, energy is released to the surroundings.

### Conclusion
The reaction \( \text{Cl} + \text{Cl} \rightarrow \text{Cl}_2 \) is an example of an exothermic reaction because it involves the release of energy as the two chlorine atoms bond to form a more stable molecule.

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