Question on Homework Problem 3.89 B, Urea

Natalie Yakobian
Posts: 45
Joined: Fri Sep 25, 2015 3:00 am

Question on Homework Problem 3.89 B, Urea

Use the information in Fig. 3.21 to estimate the bond length of (a) the CO bond in CO2; (b) the CO and CN bonds in urea, OC(NH2)2; (c) the OCl bond in HClO; (d) the NCl bond in NOCl.

Hi,
There was a similar question on this about how to solve these. However the post said that the answer to b would be 152 because of the single bond between CN, this is also what I got. However the solution manual and back of the book said that the bond would be 142 pm. Why is this?

Thanks so much!

Chem_Mod
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Re: Question on Homework Problem 3.89 B, Urea

Hey guys,
I believe they chopped off half of a sentence in the manual. What I believe it should say is that because the C atom is involved in a double bond with the oxygen, the radius would be that of a carbon with a double bond rather than a single bond. Following this approach leads you to the answer they give of 142 pm.

Natalie Yakobian
Posts: 45
Joined: Fri Sep 25, 2015 3:00 am

Re: Question on Homework Problem 3.89 B, Urea

Thank you! Is this always the case with a central atom? If its in the middle does and has a double bond with one molecule and a single bond with another does it take on the value of a double bond?