Answer:
Matter
Compound
Explanation:
Caffeine is NOT an Element, because it is formed by different elements (C, H, N, and O).
Caffeine is NOT an Isotope, because this only applies to elements with the same atomic number but different mass number.
Caffeine is Matter because it has mass and occupies space by having volume.
Caffeine is a Compound because it has a formula with a <em>definite constant composition</em> of different elements.
Answer:
Element 2
Explanation:
If we look at the model stated for element 1, it is clear that element 1 must be a noble gas. It has eight electrons in its outermost shell this implies that it has already attained a complete octet of electrons and is reluctant towards chemical reaction.
The second element belongs to group 16 since it has six electrons on its outermost shell. It is certainly more reactive than element 1 which is a noble gas.