What is the molecular geometry of IF5?

• A. Octahedral
• B. T-shaped
• C. Square pyramidal
• D. Trigonal bipyramidal

Answer: (C)

Verified step by step guidance

1. Step 1: Determine the Lewis structure of IF5 by counting the total valence electrons. Iodine (I) has 7 valence electrons, and each fluorine (F) has 7 valence electrons. Multiply the number of fluorines by 7 and add 7 for iodine to get the total valence electrons.
2. Step 2: Draw the skeletal structure with iodine as the central atom bonded to five fluorine atoms. Use single bonds to connect iodine to each fluorine atom.
3. Step 3: Complete the octets of the fluorine atoms by adding lone pairs. Each fluorine will have three lone pairs to complete its octet.
4. Step 4: Count the remaining valence electrons after bonding and assign them as lone pairs on the central iodine atom. This will give iodine one lone pair.
5. Step 5: Use the VSEPR theory to determine the molecular geometry. With five bonding pairs and one lone pair around iodine, the electron geometry is octahedral, but the molecular geometry (shape) is square pyramidal.