1B on Dino Nuggets

Moderators: Chem_Mod, Chem_Admin

Posts: 62
Joined: Wed Sep 18, 2019 12:19 am

1B on Dino Nuggets

Postby Ananta3G » Wed Nov 06, 2019 11:15 am

Hi! Can someone explain the answer to this question in a bit of detail? Thank you! Given that the length of a C–O single bond is 1.43 Å and a C=O double bond is 1.21 Å, comment on the length of the C–O bonds in carbonate.

Good luck everyone!

Brooke Yasuda 2J
Posts: 102
Joined: Sat Jul 20, 2019 12:17 am

Re: 1B on Dino Nuggets

Postby Brooke Yasuda 2J » Wed Nov 06, 2019 11:39 am

So this molecule has three resonance structures because there is a double bond and two single bonds between the carbons and oxygens. As a result, because we know that in resonance, the actual structure is a blend/hybrid of all of the resonance structures, all of the bond lengths are the same. As a result, the bond length between carbon and oxygen will be anywhere in between the length of a single bond and a double bond.

Sophia Shaka 3L
Posts: 57
Joined: Wed Sep 18, 2019 12:20 am
Been upvoted: 1 time

Re: 1B on Dino Nuggets

Postby Sophia Shaka 3L » Wed Nov 06, 2019 11:48 am

To add on to this, if you draw the Lewis structure for carbonate you'll notice 2 single C-O bonds and 1 C=O double bond. Now this might not be experimentally accurate, but a safe way to get an approximation for the resonance hybrid bond length would be to calculate the 'mean bond length': length of single bond times 2, plus length of double bond times 1, divided by number of bonds (3).
(1.43+1.43+1.21)/3 = 1.36 Å. This is a safe approximation for the resonance hybrid bond length since all the bonds have the same length and it's in between the values of a C-O single bond and C=O double bond.

Return to “Bond Lengths & Energies”

Who is online

Users browsing this forum: No registered users and 1 guest