need help with ADP.

[Bailey]

what is the net charge for adp?(i'm guessing its zero since it is a molecule)

what is the formal charge of the oxygen(the one forming a double bond with phosphate)?

can someone give me a quick reply. thanx.

[Monique]

I think:

Net charge ADP: -3
Net charge ATP: -4

I am not sure about the formal charge..

[Another God]

what is a formal charge?

[Monique]

Formal charge:

(# valence e-) - (# non-bonding e- + 1/2 # bonding e-)

you figure that one out :P

[Monique]

Actually, looking at it.. it is not so difficult.

Oxygen has 6 valence electrons.

Determine the number of nonbonding electrons and add to that the number of bonding electrons (half will belong to the O). If this number is 6, then O has a formal charge of 0. If this number is 8, O has a formal charge of -2.

But before being able to calculate anything, you'd have to write down the Lewis structure first.

[Bailey]

thanx for reply guys.
but not really sure about the -3 for adp.
i'm expecting zero for net charge.
and the formal charge of oxygen to be zero( 2 lone pair, and a double bond)

2 lone pair + 1 double bond = 8e

2 lone pair + .5 double bond = 6e

Formal charge of oxygen:

(# valence e-) - (# non-bonding e- + 1/2 # bonding e-)

(6 valence e) - (4 non-bonding e + .5(4 bonding e)) = 0

[Bailey]

adp have a net charge of zero. but when it bind with Ba (i think is Ba , not exactly sure), it will lose 3H, hence it will then have a net charge of -3.

i think the net charge of -3 probably is one that exist in nature.