Question

VSEPRT theory was proposed by

• A. Linus Pauling
• B. Moseley and Mendeleev
• C. Lewis and Kossel
• D. Sidgwick and Powell

Hint:

VSEPR theory is used to predict:
• Molecular shapes
• Bond angles
• Electron pair arrangement Key idea: \[ \text{Electron pairs repel each other} \]

Answer 1

The Correct Option is D

Concept:
VSEPRT stands for: \[ \text{Valence Shell Electron Pair Repulsion Theory} \] This theory explains:
• Shapes of molecules
• Arrangement of electron pairs
• Bond angles in covalent compounds According to this theory: Electron pairs present in the valence shell repel each other and arrange themselves as far apart as possible to minimize repulsion. The theory was proposed by: \[ \boxed{\text{Sidgwick and Powell}} \]

Step 1: Understand the purpose of VSEPR theory.
VSEPR theory helps predict molecular geometry. Examples:
• \(CH_4\) : Tetrahedral
• \(NH_3\) : Pyramidal
• \(H_2O\) : Bent shape The shapes arise because electron pairs repel one another.

Step 2: Analyze all options carefully.
Option (A): Linus Pauling
Linus Pauling is famous for:
• Hybridization
• Electronegativity concept Not VSEPR theory. Hence incorrect. Option (B): Moseley and Mendeleev
Moseley worked on atomic numbers and Mendeleev proposed periodic table. Not related to VSEPR theory. Hence incorrect. Option (C): Lewis and Kossel
They explained chemical bonding concepts and octet theory. Not VSEPR theory. Hence incorrect. Option (D): Sidgwick and Powell
They proposed the VSEPR concept. Hence this option is correct.

Step 3: Select the correct answer.
Therefore, VSEPRT theory was proposed by: \[ \boxed{\text{Sidgwick and Powell}} \] Hence, \[ \boxed{(4)\ \text{Sidgwick and Powell}} \]