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
for the second one it's F) 1.33
First one is D) -0.67
For the resonance structures of the carbonate ion, the negative charge is delocalized among the three oxygen atoms. Let's analyze each answer choice and determine if it matches the resonance structures.
A) 0: This answer choice implies no negative charge on any oxygen atom, which is incorrect.
B) -0.33: While this answer choice suggests a partial negative charge, the actual structure of the carbonate ion shows equal distribution of -1 charge on each oxygen.
C) -0.50: This answer choice suggests an even distribution of -0.5 charge for each oxygen, which is incorrect.
D) -0.67: This answer choice suggests an even distribution of -0.67 charge for each oxygen, which is incorrect.
E) -1.00: This answer choice suggests an even distribution of -1.00 charge for each oxygen, which is correct. Each oxygen atom in the carbonate ion carries a -1 charge.
F) -1.33: This answer choice suggests an uneven distribution of -1.33 charge for each oxygen, which is incorrect.
G) -1.50: This answer choice suggests an uneven distribution of -1.50 charge for each oxygen, which is incorrect.
H) -1.67: This answer choice suggests an uneven distribution of -1.67 charge for each oxygen, which is incorrect.
I) -2.00: This answer choice suggests an uneven distribution of -2.00 charge for each oxygen, which is incorrect.
Therefore, the correct answer is E) -1.00. Each oxygen in the carbonate ion carries a -1 charge.
Moving on to the second question:
What is the bond order of each carbon-oxygen bond in the carbonate ion?
A) 0: This answer choice implies no bond between carbon and oxygen, which is incorrect.
B) 0.33: This answer choice suggests a very weak bond, which is incorrect.
C) 0.50: This answer choice suggests a partially formed bond, which is incorrect.
D) 0.67: This answer choice suggests a partially formed bond, which is incorrect.
E) 1.00: This answer choice suggests a single bond between carbon and oxygen, which is correct. The bond order of each carbon-oxygen bond in the carbonate ion is 1.00.
F) 1.33: This answer choice suggests a stronger bond than a single bond, which is incorrect.
G) 1.50: This answer choice suggests a stronger bond than a single bond, which is incorrect.
H) 1.67: This answer choice suggests a stronger bond than a single bond, which is incorrect.
I) 2.00: This answer choice suggests a double bond, which is incorrect.
J) 4.00: This answer choice suggests a quadruple bond, which is incorrect.
Therefore, the correct answer is E) 1.00. The bond order of each carbon-oxygen bond in the carbonate ion is 1.00.
To determine the amount of negative charge on each oxygen atom in the carbonate ion, we need to examine the resonance structures. In the first resonance structure, we have a single negative charge on one oxygen atom. In the second resonance structure, we have another single negative charge on a different oxygen atom. In the third resonance structure, we have two negative charges distributed between two oxygen atoms.
Since the three resonance structures contribute equally to the overall structure of the carbonate ion, we need to divide the total negative charge (-2) by the number of oxygen atoms (3) to find the charge on each oxygen.
Therefore, the negative charge on each oxygen atom is -2/3 or approximately -0.67.
Answer: D) -0.67
Now let's determine the bond order of each carbon-oxygen bond in the carbonate ion. The bond order is a measure of the number of chemical bonds between a pair of atoms.
In the resonance structures of the carbonate ion, each carbon-oxygen bond is a double bond in all three structures. Since each resonance structure contributes equally, we can calculate the average bond order by adding up the bond orders from the three structures and dividing by the number of structures.
In each resonance structure, the carbon-oxygen bond order is 2 (because it is a double bond). Therefore, the average bond order is 2/3 or approximately 0.67.
Answer: D) 0.67