Chemistry Chemical Bonding DUHS 2024
PMDC Verified Question 12 of 102
The shape of an ammonia molecule is:
A
Trigonal Pyramidal
B
Tetrahedral
C
Linear
D
Planar
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option A: Trigonal Pyramidal
Concept:

Ammonia (\( ext{NH}_3 \)) has 4 electron pairs around the central nitrogen atom: 3 bonding pairs and 1 lone pair.

Solution:

  • The electron domain geometry is tetrahedral (4 electron domains).
  • However, the molecular shape (visible geometry of atoms) is Trigonal Pyramidal (or Pyramidal).
  • The lone pair repels the bonding pairs, reducing the bond angle from \( 109.5^\circ \) to \( 107^\circ \).


Why other options are incorrect:

  • Tetrahedral: Describes electron pair geometry, not molecular shape.
  • Angular: Describes 2 bonding pair + 2 lone pair molecules like \( ext{H}_2 ext{O} \).
  • Linear & Planar: Incorrect geometries for 4-domain systems with 1 lone pair.

Quality & Fidelity Assurance: Every question on BeambePrep is rigorously curated against the official PMDC syllabus with zero filler, zero out-of-syllabus content, and zero typos. When an authentic past paper originally contained a historical mistake or ambiguity from the examining board (such as UHS or NUMS), BeambePrep faithfully reflects the original paper while detailing the nuance and scientific consensus in the autopsy above.

Previous Question All Chemical Bonding MCQs Next Question

Want to solve full-length papers under timed exam conditions?

Practice with zero-scroll lockdown sprints, dynamic latency zone timers, live peer selection telemetry, and the automated Amber mistake recovery loop.

Enter Arena Sprint iOS App Android App