Question

Question 7 (d)
Which of the following materials fall in the category of a “pure substance”?
d. Hydrochloric acid

Answer 1

A pure substance is a matter in which all the constituent particles of that substance are the same in their chemical nature. They are made up of a single type of particles. Elements and compounds are classified as pure substances.
Hydrochloric acid is a compound which is composed of two elements, hydrogen and chlorine. Hence hydrochloric acid is a pure substance.