Questions: The length of a covalent bond depends upon the size of the atoms and the bond order. For each pair of covalently bonded atoms, choose the one expected to have the shorter bond length. P-1 or P-Br C-Br or P-Br

Solution Steps

The length of a covalent bond is influenced by two main factors: the size of the atoms involved and the bond order. Generally, smaller atoms form shorter bonds, and higher bond orders (e.g., double or triple bonds) result in shorter bond lengths compared to single bonds.

• Atomic Size: Iodine (I) is larger than bromine (Br) because it is located below bromine in the periodic table. Larger atoms tend to form longer bonds.
• Bond Order: Assuming both are single bonds, the bond order is the same.

Since bromine is smaller than iodine, the $\mathrm{P}-\mathrm{Br}$ bond is expected to be shorter than the $\mathrm{P}-\mathrm{I}$ bond.

• Atomic Size: Carbon (C) is smaller than phosphorus (P), which means that $\mathrm{C}-\mathrm{Br}$ bonds are likely to be shorter than $\mathrm{P}-\mathrm{Br}$ bonds.
• Bond Order: Assuming both are single bonds, the bond order is the same.

Since carbon is smaller than phosphorus, the $\mathrm{C}-\mathrm{Br}$ bond is expected to be shorter than the $\mathrm{P}-\mathrm{Br}$ bond.

Final Answer