What are the formal charges on oxygen A, carbon, and oxygen B in this resonance structure of CO2?
A. -1, 0, -3
B. +2, 0, +2
C. +1, 0, -1
D. +5, +4, +7
Click for Explanation
Formal charge = valence e– – ( e– in lone pairs + 1/2 bonded e–)
Stated more loosely, the formal charge is the number of electrons an atom “wants” to have minus the dots minus the sticks. So, for example, for the oxygen on the left, we know that oxygen “wants” to have six electrons. It’s got two dots and three sticks. So 6 – 2 – 3 = +1
A. -1, 0, -3, incorrect, Uses formal charge = -valence e– + ( e– in lone pairs + 1/2 bonded e–).
B. 2, 0, 2, incorrect, Uses formal charge = -valence e– + ( e– in lone pairs + bonded e–).
C. 1, 0, -1, correct.
D. 5, 4, 7, incorrect, Uses formal charge = e– in lone pairs + 1/2 bonded e–.
Want more MCAT practice?
We’ve got options for every schedule and learning style!
From the best online MCAT course created by top instructors with 524+ MCAT scores to the most representative full-length practice exams and private tutoring, we can custom tailor your MCAT prep to your goals!
Not sure which option is right for you? Schedule a free MCAT consultation with an MCAT expert using the form below. No obligation, just expert advice.
Related Post
Search the Blog
Free Consultation
Interested in our Online MCAT Course, One-on-One MCAT Tutoring or Med admissions packages? Set up a free consultation with one of our experienced Senior Student Advisors.
Schedule NowPopular Posts
-
-
MCAT Blog What's on the MCAT? -
-
-
MCAT Blog How to Review MCAT Full-Lengths
Free MCAT Practice Account
Need great MCAT practice?Get the most representative MCAT practice possible when you sign up for our free MCAT Account, which includes a half-length diagnostic exam and one of our full-length MCAT practice exams.
Learn More
Submit a Comment