Question

which image(s) would be considered pure substance(s)? *

Explanation:

A pure - substance is either an element (composed of only one type of atom) or a compound (composed of two or more types of atoms in a fixed ratio). Image 4 shows a mixture of two different substances (two different types of molecules). Image 1 shows a mixture of different substances (a compound and an element). Image 2 shows a mixture of two different elements. Image 3 shows a compound (a pure - substance as all the molecules are identical). Image 5 shows an element (a pure - substance as all the atoms are identical).

Answer:

3&5