Chemical formula table
Substance Formula/Symbol
Iron Fe
Sodium chloride NaCl
Carbon dioxide CO2
Aluminum Al

The table lists the chemical formulas or symbols of a few common substances. Which two substances are compounds?

A) aluminum and iron
B) iron and sodium chloride
C) carbon dioxide and aluminum
D) sodium chloride and carbon dioxide

atomic number of carbon is 6

electronic configuration of carbon is 1s²2s²2p²

orbital diagram of c is as shown here in the image.

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