Which element is the most reactive?
sodium
nickel
carbon
oxygen

Sodium .

i would say b

explanation:

but i think i would need more information than that

the number of protons in the nucleus of a given element. has slight luster and conducts electricity at high temperatures like metal.but like a nonmetal,boron is brittle and does not conduct electricity well at low temperatures. in graphite, carbon is a soft,brittle solid.it is reflective,ductile,or malleable.