A sample of formic acid (CH2O2) contains 4.05 x 1020 molecules. How many moles of formic acid are in this sample? Be careful: round to the nearest 0.00001 and
include both units and substance in your answer.

what does the table look like

its first and third is your answer i did the qustion the fourth isnt right

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!

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