Answer
a) i
b) v, vi
c) iv
d) ii, iii
Work Step by Step
The question here deals with visualizing what represents a pure element, and a compound.
A pure element contains only one type of atom in it. It is important to remember that an element can be monatomic or molecular in form. It is monatomic if each unit is an unattached atom while it is molecular in form if the element has two or more of the same element atoms bonded together. Some elements exist naturally as molecules such as oxygen. Oxygen is a diatomic molecule, O2.
A compound, on the other hand, contains more than one type of atom in a molecule.
Figure (i) is a diatomic element.
Figure (ii) consists of two types of molecules - diatomic element (blue-blue molecule) and a compound (brown-blue molecule)
Figure (iii) consists of atomic element (blue sphere) and a compound (brown-blue molecule)
Figure (iv) shows a compound (brown-blue molecule)
Figure (v) shows two types of monatomic elements (blue spheres and brown spheres)
Figure (vi) shows two types of monatomic elements (blue spheres and brown spheres)
