Concept:Matter is classified by its composition. Molecules made up of identical atoms are elements, while molecules composed of different types of atoms chemically bonded together are compounds.
Formula:$$ \text{N (Nitrogen)} + 3\text{H (Hydrogen)} \rightarrow \text{NH}_3 \text{ (Ammonia)} $$
Solution:- Ammonia (\( \text{NH}_3 \)) consists of two entirely distinct elements from the periodic table: Nitrogen and Hydrogen.
- Because it contains more than one type of element chemically bonded together, it acts as a heteroatomic molecule.
- Therefore, it falls under the strict chemical definition of a "molecule of a compound".
Why other options are incorrect:- Molecule of atoms: Vague terminology; all molecules consist of atoms.
- Molecule of element: This applies to homoatomic molecules like \( \text{O}_2 \) or \( \text{N}_2 \), where only one type of element is present.
- Molecule of ion: \( \text{NH}_3 \) is electrically neutral (zero charge), therefore it is not an ion.
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.