VSEPR (Valence Shell Electron Pair Repulsion) theory explains molecular shapes by stating that electron pairs in the valence shell of a central atom repel each other, therefore arranging themselves to minimize repulsions.
• Lone pairs, triple bonds, double bonds and single bonds create a hierarchy of repulsive forces between electron pairs.
• Lone pairs: Experience the strongest repulsive forces because they are only held by one nucleus and occupy a large space around the central atom.
• Multiple bonds (triple and double bonds): They create more repulsion than single bonds because they have a higher electron density.
• Therefore, the order of repulsion is: Lone pair > Triple Bond > Double Bond > Single bond. Therefore, statements B and C are correct, and A and D are incorrect.
List-I (Type of Crystalline Solid) | List-II (Example) |
(A) Ionic | (III) Sodium Chloride, NaCl |
(B) Covalent | (IV) Diamond, C |
(C) Molecular | (I) Methane, CH4 |
(D) Metallic | (II) Copper, Cu |
List-I | List-II |
(A) Principal Quantum Number (n) | (ii) 1, 2, 3,... |
(B) Azimuthal Quantum Number (l) | (iv) 0, 1, 2,... n - 1 |
(C) Magnetic Quantum Number (ml) | (iii) 0, ± 1, ± 2, ± 3,..., ± 1 |
(D) Spin Quantum Number (s) | (i) -1/2, +1/2 |
Choose the correct answer from the options given below:
List-I | List-II |
---|---|
(A) CCl4 | (i) Insecticide |
(B) CF2Cl2 | (ii) Refrigerant |
(C) CHI3 | (iii) Antiseptic for wounds |
(D) CH2Cl2 | (iv) Propellant for aerosols |
Europium (Eu) resembles Calcium (Ca) in the following ways:
(A). Both are diamagnetic
(B). Insolubility of their sulphates and carbonates in water
(C). Solubility of these metals in liquid NH3
(D). Insolubility of their dichlorides in strong HCI
Choose the correct answer from the options given below: