5. The effect on indoor air quality of off-gassing from new synthetic building materials is a concern because of the release of

A)carbon dioxide

B)NOX gases

C) water vapour

D)volatile organic compounds

iron and sleel

make siroeel

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