The C2 molecule has a MO diagram similar to N2 (Figure 8.22a). What is the bond order of C2 and is it paramagnetic or diamagnetic? (LO 8.12) (a) Bond order = 2, diamagnetic (b) Bond order = 2, paramagnetic (c) Bond order = 0, paramagnetic (d) Bond order = 3>2, diamagnetic

Verified step by step guidance

1. Step 1: To determine the bond order and magnetic property of a molecule, we need to understand its molecular orbital (MO) diagram. The MO diagram of C2 is similar to that of N2. In the MO diagram, we fill the molecular orbitals with the total number of valence electrons from both carbon atoms. Each carbon atom has 4 valence electrons, so we have a total of 8 electrons to fill in the MO diagram.
2. Step 2: The filling order of the molecular orbitals is as follows: σ1s, σ*1s, σ2s, σ*2s, π2p, σ2p, π*2p, σ*2p. Fill the orbitals from lowest to highest energy until all 8 electrons are used. Remember that each orbital can hold a maximum of 2 electrons and the π2p orbital is doubly degenerate, meaning it can hold 4 electrons.
3. Step 3: After filling the orbitals, calculate the bond order. The bond order is given by the formula: (number of electrons in bonding orbitals - number of electrons in antibonding orbitals) / 2.
4. Step 4: To determine whether the molecule is paramagnetic or diamagnetic, look at the number of unpaired electrons in the MO diagram. If there are unpaired electrons, the molecule is paramagnetic. If all electrons are paired, the molecule is diamagnetic.
5. Step 5: Apply the information from steps 3 and 4 to the given answer choices to find the correct one. Remember not to calculate the final result, but use the steps to guide you to the correct answer.

Key Concepts

Molecular Orbital Theory

Molecular Orbital (MO) Theory describes the behavior of electrons in molecules, where atomic orbitals combine to form molecular orbitals that can be occupied by electrons. These orbitals are classified as bonding, antibonding, or non-bonding, and their occupancy determines the stability and properties of the molecule, including bond order and magnetic behavior.

Bond Order

Bond order is a measure of the number of chemical bonds between a pair of atoms, calculated as the difference between the number of bonding and antibonding electrons divided by two. A higher bond order indicates a stronger bond and greater stability of the molecule. For example, a bond order of 2 suggests a double bond.

Paramagnetism and Diamagnetism

Paramagnetism and diamagnetism are terms that describe the magnetic properties of substances based on their electron configurations. Paramagnetic substances have unpaired electrons, making them attracted to magnetic fields, while diamagnetic substances have all paired electrons, causing them to be weakly repelled by magnetic fields. The presence of unpaired electrons is crucial for determining a molecule's magnetic behavior.