Simple question but why do some elements in an equation have parenthesis around them? Do they have any use?
(Why does OH have a parenthesis around it?)

20 drops hope this

56 moles of   lieter in chemistry

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

that's it!

if you need further assistance, let me know: )

~ trueboss72