CHEM 103 Chapter Notes - Chapter M8Q3: Chemical Polarity, Nitrite, Weighted Arithmetic Mean

Bond order corresponds to the type of bond. Single bonds have a bond order of 1, double bonds have a bond order of 2, and triple bonds have a bond order of 3. A higher bond order corresponds to higher bond energy. Therefore triple bonds are stronger than double bonds, which are stronger than single bonds. A higher bond order corresponds to a shorter bond length. Therefore triple bonds are the shortest, and single bonds are the longest.

The bond order of I2 is .

The bond order of S2 is .

The bond order of P2 is

1. Draw a Lewis structure for the ozone molecule, O₃. (The order of atom attachment is O—O—O and they do not form a ring.) Chemists use ozone to cleave carbon-carbon double bonds. 
2. Draw four contributing resonance structures; including formal charges.  
3. How does the resonance model account for the fact that the length of each O—O bond in ozone (128pm) is shorter than the O—O single bond in hydrogen peroxide (HOOH, 147pm) but longer than the O—O the double bond in the oxygen molecule (123pm)?