Carbon atoms have four valence electrons. Oxygen atoms have six valence electrons. Carbon and oxygen can share electrons so that each atom obtains a full outer shell of 8 valence electrons. Draw the shared electrons on this diagram

Answer:
See explanation.
Explanation:
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In this case, since both carbon and oxygen need to complete the octet, that is sharing eight electrons in total, since carbon has four valence electrons it has a double bond with one oxygen so it also allows the first oxygen to attain the octet; moreover, for the other oxygen, there also a double bond in order to complete the octet for carbon and for the second oxygen as shown on the attached picture.
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