Question

Predict the correct order among the following:

• A. lone pair-lone pair > bond pair-bond pair > lone pair - bond pair
• B. bond pair - bond pair > lone pair - bond pair > lone pair - lone pair
• C. lone pair - bond pair > bond pair - bond pair > lone pair - lone pair
• D. lone pair - lone pair > lone pair - bond pair > bond pair - bond pair

Answer 1

The Correct Option is D

The question presents us with different interactions between electron pairs and asks us to predict the correct order of repulsions. In molecular chemistry, the VSEPR (Valence Shell Electron Pair Repulsion) theory is used to explain the structure of molecules. The theory states that electron pairs around a central atom will arrange themselves to be as far apart as possible to minimize repulsive forces. The order of repulsion strength among electron pairs is an important aspect of VSEPR theory.

Here's the correct order based on repulsion strength:

1. Lone pair-lone pair (lp-lp): The repulsion is strongest because lone pairs occupy more space around the nucleus, leading to greater repulsive interactions.
2. Lone pair-bond pair (lp-bp): These interactions are weaker than lp-lp repulsions but stronger than bp-bp repulsions because lone pairs are still involved.
3. Bond pair-bond pair (bp-bp): This is the weakest repulsion as bond pairs are involved in electron sharing between two atoms, allowing less freedom to repel each other.

Thus, according to VSEPR theory, the predicted order of electron pair repulsion strength is:

lone pair - lone pair > lone pair - bond pair > bond pair - bond pair.

This matches the correct answer from the options provided.