Which of the following are possible Lewis structures for a molecule with the formula C₂H₆O? A) 1 B) 2 C) 3 D) 2 and 3 E) 1,2,and 3

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Quizplus · Accepted Answer

It is impossible to determine the Lewis structure of a molecule just from its formula, since there are many possible ways that the atoms can be arranged. However, we can use the molecular formula to determine the total number of valence electrons in the molecule, and use this information to narrow down the possibilities. The molecular formula C₂H₆O contains a total of 48 valence electrons (6 from carbon, 1 from sulfur, 12 from boron, 1 from hydrogen, 16 from sulfur, and 12 from oxygen). We can use this information to generate possible Lewis structures for the molecule. One possible Lewis structure is shown below: S=B-O-C=S | | HS SBHS This structure has a total of 48 valence electrons and satisfies the octet rule for all of the atoms except for boron, which has only six electrons in its outer shell. However, boron is known to frequently form compounds in which it has fewer than eight valence electrons, so this structure is a plausible option. Another possible Lewis structure is shown below: S-B=S=C-O | | HS SBHS This structure also has a total of 48 valence electrons and satisfies the octet rule for all of the atoms except for boron, which again has only six electrons in its outer shell. Like the first structure, this structure is a plausible option for the molecule. There may be other Lewis structures that are also possible for this molecule, but these two provide reasonable options based on the available information. Therefore, the correct answer is D, which indicates that options 2 and 3 are possible Lewis structures for the molecule.

Which of the Following Are Possible Lewis Structures for a Molecule