Geometric Model (First Year Chem) Questions

[vexx]

Hi.

I think i slightly fail as i don't understand this question (It's got a few parts to it)

For the Formic Acid, CHOOH:
Firstly, verification: Is the parent geometry for the carbon atom: trigonal planar and for hydroxyl oxygen: tetrihedral?
And the molecular geometry for carbon: trigonal planar and for hydroxyl oxygen: bent?
If i am wrong, why is it something else?

Ok questions (these i have no idea ) :
1. Formic acid can be deprotonated in alkali environments. Use a diagram to draw this structure, including any resonance structures. Also, draw the overall delocalised structure for the species.
2. What is the bond order for the formate ion (hint: ozone example from a lecture done)?
(we haven't attended any lectures or anything lol)

These are the two last questions for our second prac report, and i am so confused by them.

Thanks

Vexx

[Edmund]

Ok questions (these i have no idea ) :
1. Formic acid can be deprotonated in alkali environments. Use a diagram to draw this structure, including any resonance structures. Also, draw the overall delocalised structure for the species.
2. What is the bond order for the formate ion (hint: ozone example from a lecture done)?
(we haven't attended any lectures or anything lol)

These are the two last questions for our second prac report, and i am so confused by them.

Thanks

Vexx

1.



The first structure I've drawn is formic acid, then deprotonated meaning it lost a H⁺. Now it has an unpaired electron on the oxygen then can 'move' as shown by the arrows. This leads to a chain reaction where it causes the electrons from the double bond to move up to the oxygen atom (as shown by the arrows again). Why? The structure wants to be in the more stable position.

2.

Bond order is the number of bonds between two atoms. So for the formate ion,

C=O has a bond order of 2, C-O has a bond order of 1 and C-H has a bond order of 1

[vexx]

Thank you edmund!! That makes perfect sense.

Umm sorry one more question (also about CHOOH)

- Two stereoisomers exist for this molecule, known as syn and anti. Suggest what these two geometries would look like using diagrams. (i haven't heard of syn and anti before :| )

[Edmund]

Thank you edmund!! That makes perfect sense.

Umm sorry one more question (also about CHOOH)

- Two stereoisomers exist for this molecule, known as syn and anti. Suggest what these two geometries would look like using diagrams. (i haven't heard of syn and anti before :| )

No idea, maybe have a look on Wikipedia? hehe

http://en.wikipedia.org/wiki/Syn_and_anti_addition

[vexx]

Haha ok i'll search about again.

Thanks anyway.

oh btw, syn=cis, and anti=trans (apparently) if that means anything.. lol

[Edmund]

Haha ok i'll search about again.

Thanks anyway.

oh btw, syn=cis, and anti=trans (apparently) if that means anything.. lol

Yeah, same idea, but I think syn and anti are for double/triple bonds

[Mao]

Some clarifications:

Bond order - in terms of molecular orbitals, , you can then generalize this that single bond = 1, double bond = 2, etc
In the case for the formate ion, because of resonance structures, the bond order of the C-O/C=O bond is actually 1.5

Attached are the two stereoisomers.