Air is made of of gaseous elements and compounds that interact but are not bound to each other. so air can be considered a
a.) colloid
b.) mixture
c.) solution
d.) suspension

Answer;

A mixture

Explanation;Air is made of of gaseous elements and compounds that interact but are not bound to each other. So air can be considered a Mixture.A mixture is a combination of two or more substances that are not chemically combined, such that the substances in it are not bound to each other.A mixture may be homogeneous or heterogeneous; in a homogeneous mixture all the components of the mixture are in the same phase while in a heterogeneous mixture the components are in different phase such as in the case of suspension. Air is a mixture because the compounds that make up air such as nitrogen, oxygen, carbon dioxide, etc are not chemically combined, they are not bound to each other. It is a homogeneous mixture because or the substances in air are in a single phase, gaseous state.

You use the atomic number to find out how many protons and neutrons there are in the atom. you use the atomic mass to find out how many protons and electrons there are in the atom.