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.
Match List I with List II:
Choose the correct answer from the options given below:
Match List I with List II:
Choose the correct answer from the options given below:
Which of the following statements are true?
A. Unlike Ga that has a very high melting point, Cs has a very low melting point.
B. On Pauling scale, the electronegativity values of N and C are not the same.
C. $Ar, K^{+}, Cl^{–}, Ca^{2+} and S^{2–}$ are all isoelectronic species.
D. The correct order of the first ionization enthalpies of Na, Mg, Al, and Si is Si $>$ Al $>$ Mg $>$ Na.
E. The atomic radius of Cs is greater than that of Li and Rb.
Choose the correct answer from the options given below:
Match List-I with List-II\[\begin{array}{|c|c|} \hline \textbf{Provision} & \textbf{Case Law} \\ \hline \text{(A) Strict Liability} & \text{(1) Ryland v. Fletcher} \\ \hline \text{(B) Absolute Liability} & \text{(II) M.C. Mehta v. Union of India} \\ \hline \text{(C) Negligence} & \text{(III) Nicholas v. Marsland} \\ \hline \text{(D) Act of God} & \text{(IV) MCD v. Subhagwanti} \\ \hline \end{array}\]
Match Fibre with Application.\[\begin{array}{|l|l|} \hline \textbf{LIST I} & \textbf{LIST II} \\ \textbf{Fibre} & \textbf{Application} \\ \hline \hline \text{A. Silk fibre} & \text{I. Fire retardant} \\ \hline \text{B. Wool fibre} & \text{II. Directional lustre} \\ \hline \text{C. Nomex fibre} & \text{III. Bulletproof} \\ \hline \text{D. Kevlar fibre} & \text{IV. Thermal insulation} \\ \hline \end{array}\]