The factor that affects how easily an electron can be removed from an atom is the
a. structure of the atom.
b. size of the atom.
c. temperature of the environment.
d. surrounding atoms.

A.  Structure of the atom determines how easily an electron can be removed from an atom.

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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