Electron Bond Breaking: Valency Creation

When an electron breaks away from a covalent bond, it leaves behind a specific consequence at the location of the bond.

Broken Covalent Bond Consequence

A covalent bond involves shared electrons between atoms. When an electron leaves this shared pair and moves away:

• A vacancy or hole is created where the electron used to be.
• This hole represents a site where an atom now has an incomplete valence shell.
• This incomplete valence state is described as a created valency at the broken bond site.

Valency Creation Option Analysis

Evaluating the options based on the physical process:

• Option 1 is incorrect: While conductivity changes, it doesn't necessarily become a full conductor.
• Option 2 is correct: The vacancy left by the electron represents an unsatisfied bonding capability, hence a created valency.
• Option 3 is partially true but less direct: Conductivity increases due to the mobile hole, but the primary creation is the valency at the site.
• Option 4 is incorrect: Typically, ions are not directly produced; rather, charge carriers like holes are formed.

Therefore, the most accurate description is the creation of a valency in the broken covalent bond.