15Q= 1s2 2s2 2p6 3s2 3p3
18T=
23A=
6X=
3G=
31L=
84D=
12M=

what grade are you in

Explanation:

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