Question

Both carbon dioxide and water are pure substances. how are they similar to each other?

a.both substances have a set ratio of atoms that cannot be separated.
b.both substances have a set ratio of atoms that can be separated.
c.both substances have the same physical and chemical properties.
d.both substances have the same physical properties, but different chemical properties.

Answer 1

The answer is a.

Pure substances, by definition, are made of only one kind of atom/molecule, and cannot be broken down. Thus, their atoms cannot be separated.

b is incorrect because the atoms can't be separated.
c and d are incorrect because carbon dioxide and water do not have similar physical properties.