Question

4x The formulas for three different materials are shown below.
COz
NaCl
HCI
These may all be classified as


Ax A elements and compounds.


elements and molecules.

C
elements and pure substances.
4x

D compounds and pure substances.

Answer 1

The correct classification for the substances CO₂ (carbon dioxide), NaCl (sodium chloride), and HCl (hydrochloric acid) is:

**D - compounds and pure substances.**

All three substances are compounds because they consist of two or more different elements chemically bonded together. They are also considered pure substances because they have a consistent and uniform chemical composition.