Answer:
The answer to your question is below
Step-by-step explanation:
1) Neon is a noble gas that has 8 electrons in its outermost shell. Atoms are stable when they have 8 electrons in that shell. So Neon does not need to react to become stable.
Oxygen has 6 valence electrons so it needs to gain two electrons to become stable, which makes is why oxygen is fairly reactive.
2.- As I mention before, atoms are stable when they reach 8 electrons in their outermost shell. Beryllium has 2 electrons in that shell so it is easier to lose 2 electrons rather than gain 6 electrons. Sulphur has 6 valence electrons so for it is easier to gain 2 electrons rather than gain 6.
3.- Both fluorine and chlorine are located in the 17th group of the periodic table, elements in the same group have similar chemical and physical properties.