AP Chemistrymediummcq1 pt
Which molecule contains a central atom with an expanded octet, meaning more than eight electrons around it?
A.CH₄ (methane)
B.NH₃ (ammonia)
C.SF₆ (sulfur hexafluoride)
D.OF₂ (oxygen difluoride)
Explanation
Core Concept
Sulfur, a period 3 element, bonds to six fluorines and surrounds itself with twelve shared electrons. Third-period atoms are large enough to accommodate more than four bonding partners, so their octet ceiling lifts. Period 2 central atoms such as carbon, nitrogen, oxygen, and boron can never exceed eight electrons because only four orbitals are available.
Correct Answer
CSF₆ (sulfur hexafluoride)
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