Question

Match List-I with List-II.

List-I (Molecule)	List-II (Shape)
(A) \(NH_3\)	(I) Square pyramid
(B) \(BrF_5\)	(II) Tetrahedral
(C) \(PCL_5\)	(III) Trigonal pyramidal
(D) \(CH_4\)	(IV) Trigonal bipyramidal

Choose the correct answer from the options given below:

• A. A-IV, B-III, C-I, D-II
• B. A-II, B-IV, C-I, D-III
• C. A-III, B-I, C-IV, D-II
• D. A-III, B-IV, C-I, D-II

Answer 1

The Correct Option is C

To solve this question, we need to determine the correct shape for each molecule listed in List-I based on their molecular geometry, and then match them with the options in List-II. We will assess each molecule's electron pair and bond pair geometries:

1. \(NH_3\) (Ammonia):
   • Ammonia (\(NH_3\)) has a total of 5 valence electrons from Nitrogen and 1 valence electron from each of the 3 Hydrogens, making a total of 8 valence electrons.
   • Nitrogen forms 3 sigma bonds with Hydrogen atoms and has one lone pair of electrons.
   • The molecular geometry is Trigonal Pyramidal due to the lone pair that slightly distorts the angles. Thus, the shape for \(NH_3\) is III) Trigonal Pyramidal.
2. \(BrF_5\) (Bromine Pentafluoride):
   • In \(BrF_5\), the central atom Bromine has 7 valence electrons and bonds with 5 Fluorine atoms, using 5 electrons in bonding.
   • There is 1 lone pair remaining on Bromine.
   • The electron pair geometry is Octahedral, but due to the presence of a lone pair, its molecular geometry is a Square Pyramidal. Thus, the shape for \(BrF_5\) is I) Square Pyramid.
3. \(PCl_5\) (Phosphorus Pentachloride):
   • Phosphorus has 5 valence electrons and forms 5 bonds with Chlorine atoms with no lone pairs remaining.
   • This yields a geometric structure that is Trigonal Bipyramidal with the Chlorine atoms.
   • Thus, the shape for \(PCl_5\) is IV) Trigonal Bipyramidal.
4. \(CH_4\) (Methane):
   • The central atom Carbon forms 4 sigma bonds with Hydrogen atoms with no lone pairs.
   • This results in a geometry that is Tetrahedral.
   • Thus, the shape for \(CH_4\) is II) Tetrahedral.

Matching these descriptions with List-II, we get:

• A) \(NH_3\) - III) Trigonal Pyramidal
• B) \(BrF_5\) - I) Square Pyramid
• C) \(PCl_5\) - IV) Trigonal Bipyramidal
• D) \(CH_4\) - II) Tetrahedral

The correct answer is: A-III, B-I, C-IV, D-II.

Answer 2

NH$_3$: Trigonalpyramidal ({sp}$^3$ hybridization with one lone pair on N).
BrF$_5$: Squarepyramidal ({sp}$^3${d}$^2$ hybridization with one lone pair on Br).
PCl$_5$: Trigonalbipyramidal ({sp}$^3${d} hybridization, no lone pairs).
CH$_4$: Tetrahedral ({sp}$^3$ hybridization, no lone pairs).
Matching: A-III, B-I, C-IV, D-II.
Final Answer: A-III, B-I, C-IV, D-II.