Question

Which of the following should be classified as a mixture? water air iron helium

Answer 1

air is a mixture because it is made up of many constituents like oxygen, argon etc. it can be physically separated by fractional distillation. it doesnt have a formula unlike compounds and elements. its composition varies differently with its constituents.

Answer 2

Answer: air

Step-by-step explanation:

A mixture is a combination of two or more substances. When substances mix together it results in a change in their physical as well as chemical form. A mixture exhibit a chemical and physical form different from the constituent substances.

An air is a mixture of gases. It forms a part of the atmosphere. Air may contain gases like carbon dioxide, water vapors, nitrogen, oxygen, and others.