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Chemistry · CHEMICAL BONDING AND MOLECULAR STRUCTURE

हिन्दी

Which of the following molecules has an incomplete octet for the central atom?

  1. \( \text{SF}_6 \)
  2. \( \text{PF}_5 \)
  3. \( \text{BeH}_2 \)
  4. \( \text{H}_2\text{SO}_4 \)

Correct answer · Option 3

\( \text{BeH}_2 \)

Explanation

In \( \text{BeH}_2 \), beryllium shares 2 pairs of electrons, surrounding it with only 4 valence electrons, representing an incomplete octet.

Related questions

Consider the following statements regarding hybridization and orbital characteristics: (A) Hybrid orbitals are always equivalent in energy and shape. (B) Promotion of an electron is an essential condition prior to hybridization. (C) A \( \pi \) bond is stronger than a \( \sigma \) bond because of greater extent of orbital overlap. (D) Only half-filled orbitals of valence shell take part in hybridization; fully filled orbitals can never participate. Which of the above statements is/are correct?→Consider the following isoelectronic pairs/species: \( \text{N}_2 \), \( \text{CO} \), \( \text{NO}^+ \), \( \text{F}_2 \), and \( \text{O}_2^{2-} \). Let \( S_1 \) be the sum of bond orders of \( \text{N}_2 \), \( \text{CO} \), and \( \text{NO}^+ \), and \( S_2 \) be the sum of bond orders of \( \text{F}_2 \) and \( \text{O}_2^{2-} \). What is the value of \( S_1 - 2S_2 \)?→In terms of orbital overlap and bond directionality, which statement explains why simple atomic orbital overlap fails to describe the geometry of \( \text{CH}_4 \)?→Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Two isolated hydrogen atoms do not form a bond when their total potential energy increases as they approach each other. Reason (R): A covalent bond between two atoms is formed only when the net attractive forces overcome the repulsive forces and the system acquires minimum potential energy. In the light of the above statements, choose the correct answer from the options given below:→
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