Consider the resonance structures for the carbonate ion.
O--C-O(-)
l
O(-)
(-)O-C--O
l
O(-)
(-)O-C-O(-)
l
l
O
How much negative charge is on each oxygen of the carbonate ion?
A)0,
B) -.33,
C)-.50,
D) -.67,
E)-1.00,
F)-1.33,
G)-1.50,
H)-1.67,
I)-2.00
What is the bond order of each carbon oxygen bond in the carbonate ion?
A)0,
B).33,
C).50,
D).67,
E)1.00,
F)1.33,
G)1.50,
H)1.67,
I)2.00,
J)4.00
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yiuioiu
To determine the negative charge on each oxygen atom in the carbonate ion, we need to consider the resonance structures. In this case, carbonate ion has three resonance structures, and the negative charge is spread out among the oxygen atoms.
Resonance structure 1:
O(-)
|
O -- C -- O
Resonance structure 2:
(-) O
|
O -- C -- O
Resonance structure 3:
(-) O
|
O -- C -- O(-)
In resonance structure 1 and 2, each oxygen atom has a partial negative charge (-0.5 on each oxygen atom). In resonance structure 3, the oxygen atom on the right has a full negative charge (-1).
To determine the total negative charge on each oxygen atom, we sum up the contributions from each resonance structure.
For the oxygen atoms in resonance structures 1 and 2:
((-0.5) + (-0.5)) / 2 = -0.5
For the oxygen atom in resonance structure 3:
(-1)
Therefore, the negative charge on each oxygen atom of the carbonate ion is -0.5 and -1.
Now, let's determine the bond order of each carbon-oxygen bond in the carbonate ion. Bond order represents the number of electron pairs that hold two atoms together.
In all three resonance structures, there are two carbon-oxygen bonds. The bond order is the total number of bonds divided by the number of resonance structures.
Total number of carbon-oxygen bonds: 2
Number of resonance structures: 3
Bond order = 2/3 = 0.67
Thus, the bond order of each carbon-oxygen bond in the carbonate ion is approximately 0.67.
In summary:
Negative charge on each oxygen atom: -0.5 and -1
Bond order of each carbon-oxygen bond: 0.67
Therefore, the correct answer choices are:
Negative charge on each oxygen atom: G) -1.50, H) -1.67
Bond order of each carbon-oxygen bond: D) 0.67