1. A 6. D 11. B
2. D 7. B 12. B
3. B 8. D 13. A
4. D 9. B 14. A
5. C 10. C
1. (a) Ar; Group 0: Noble gases
(b) It has a stable octet electronic configuration, so it does not need to form a molecule or form ions.
(c) EDIT QUESTION TO: MOLECULES OF AN ELEMENT, NOT COMPOUNDS OF AN ELEMENT
Ozone, Nitrogen and Oxygen.
(d) Carbon dioxide and Sulfur dioxide
(e) Nitrogen (RMM: 28)
(f) Sulfur dioxide (RMM: 64)
2. C is a pure element.
E is a mixture of two monoatomic elements.
No pure compound is present.
A is a mixture of two compounds.
D/ B is a mixture of a compound and an element.
3. There are 4 diagrams, referred here as top left, top right, bottom left and bottom right.
In the top left diagram, molecules of a compound are present.
In the top right diagram, molecules of an element are present.
In the bottom left diagram, a mixture of monoatomic elements are present.
In the bottom right diagram, molecules of an element are present.