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Multiple Choice
Given the following molecules, which has the longest bond between the two atoms indicated?A) O_2 (oxygen-oxygen bond)B) N_2 (nitrogen-nitrogen bond)C) NO (nitrogen-oxygen bond)D) O_2^{2-} (oxygen-oxygen bond in peroxide)
A
N_2 (nitrogen-nitrogen bond)
B
NO (nitrogen-oxygen bond)
C
O_2^{2-} (oxygen-oxygen bond in peroxide)
D
O_2 (oxygen-oxygen bond)
Verified step by step guidance
1
Understand that bond length is influenced by bond order: higher bond order means shorter bond length, and lower bond order means longer bond length.
Determine the bond order for each molecule using the formula: \(\text{Bond order} = \frac{\text{number of bonding electrons} - \text{number of antibonding electrons}}{2}\).
For \(O_2\), \(N_2\), \(NO\), and \(O_2^{2-}\), write their molecular orbital electron configurations or use known bond orders: \(N_2\) has a bond order of 3, \(O_2\) has a bond order of 2, \(NO\) has a bond order of 2.5, and \(O_2^{2-}\) (peroxide ion) has a bond order of 1.
Compare the bond orders: the molecule with the lowest bond order will have the longest bond length because fewer bonding electrons result in a weaker and longer bond.
Conclude that since \(O_2^{2-}\) has the lowest bond order (1), it will have the longest bond length among the given molecules.