Which of the following best describes the Valence Shell Electron Pair Repulsion (VSEPR) theory?

• A. It is a model used to predict the shapes of molecules based on the repulsion between electron pairs in the valence shell of the central atom.
• B. It is a rule that states atoms tend to achieve a noble gas electron configuration by gaining, losing, or sharing electrons.
• C. It is a method for determining the molecular mass of compounds by analyzing their chemical formulas.
• D. It is a theory that explains the energy levels of electrons in atoms using quantum mechanics.

Answer: (A)

Verified step by step guidance

1. Identify the main purpose of the Valence Shell Electron Pair Repulsion (VSEPR) theory, which is to explain molecular shapes.
2. Understand that VSEPR theory focuses on the repulsions between electron pairs (bonding and lone pairs) in the valence shell of the central atom in a molecule.
3. Recognize that these electron pairs arrange themselves to minimize repulsion, which determines the geometry or shape of the molecule.
4. Compare the given options to see which one aligns with this explanation: the correct description should mention predicting molecular shapes based on electron pair repulsions.
5. Conclude that the best description is the one stating that VSEPR is a model used to predict molecular shapes based on repulsions between electron pairs in the valence shell of the central atom.