NEETChemistryChemical Bonding and Molecular Structure
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): XeF ₂ has a linear shape with zero dipole moment, even though its central atom possesses three lone pairs of electrons. Reason (R): According to VSEPR theory, the three lone pairs in XeF ₂ occupy the equatorial positions of a trigonal bipyramidal geometry to minimize lone pair - lone pair repulsion
Options
- ABoth Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).
- BBoth Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
- CAssertion (A) is true but Reason (R) is false.
- DAssertion (A) is false but Reason (R) is true.
Correct answer
B. Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
Step-by-step solution
Assertion (A) is true: In XeF ₂ , the central xenon atom has 8 valence electrons. It forms 2 single bonds with fluorine atoms, leaving 6 non-bonding electrons, which corresponds to 3 lone pairs. The molecule has a perfectly linear shape, making it symmetrical. As a result, the individual Xe-F bond dipoles cancel each other out, leading to a net zero dipole moment. Reason (R) is true: The central atom in XeF ₂ has 2 bond pairs and 3 lone pairs (steric number = 5), which corresponds to a trigonal bipyramidal electron