# Reactivity Dilemma of elements [closed]

While learning Periodic Properties, I stumbled upon a doubt regarding reactivity of elements of period 2 and period 3.

(I am denoting reactivity, of any $$X$$ element as $$R_{X}$$.)

For reactivity of $$s-block$$ elements, I saw $$R_{Li} . Acording to me this is so because since the metallic character increases down the group, (Am i correct $$?$$)

But as we go towards right side, things become complicated. For boron group, I saw this: $$R_{B}. I Similarly for other groups I saw following: $$R_{N}; $$R_{O}>R_{S}$$; $$R_{F}>R_{Cl}$$;

(According to me reactivity of third period elements should be greater than that of second period but i don't know why it doesn't follow for oxygen and halogen groups)

Please tell reasons why there is such unusual recativity trend for the elements I mentioned, and thanks in advance $$!!$$

(I saw on internet having divided opinions, which was not helpful).

$$\ce{Li}$$ vs $$\ce{Na}$$, $$\ce{Be}$$ vs $$\ce{Mg}$$, $$\ce{B}$$ vs $$\ce{Al}$$:
$$\ce{N}$$ vs $$\ce{P}$$, $$\ce{O}$$ vs $$\ce{S}$$, $$\ce{F}$$ vs $$\ce{Cl}$$: