Rank the following series of molecules or ions in order of decreasing bond energy using their bond order to predict relative magnitude: chlorine: Cl2, sulfur: S2, phosphorus: P2.

P2>S2>Cl2 is the order of bond energy of the given molecules.

Explanation:

The bonding in each molecule is shown below:

Thus, between each P-atom, there exists a triple bond.

Between two S-atoms there exists a double bond.

Between two chlorine atoms, there exists a single bond.

As the number of bonds increases between the given atoms, then bond energy required to break the bonds also increases.

Thus, the bond order is shown below:

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