Which of the following statements correctly describes the Lewis dot structure of the neutral compound ICl_5?

• A. The central iodine atom is surrounded by five chlorine atoms and one lone pair.
• B. The central iodine atom is surrounded by six chlorine atoms and no lone pairs.
• C. The central iodine atom is surrounded by four chlorine atoms and two lone pairs.
• D. The central iodine atom is surrounded by five chlorine atoms and no lone pairs.

Answer: (A)

Verified step by step guidance

1. Identify the central atom in the compound ICl_5. Since iodine (I) is less electronegative than chlorine (Cl), iodine will be the central atom.
2. Determine the total number of valence electrons available. Iodine has 7 valence electrons, and each chlorine atom has 7 valence electrons. For ICl_5, total valence electrons = 7 (I) + 5 × 7 (Cl) = 7 + 35 = 42 electrons.
3. Draw single bonds between the central iodine atom and each of the five chlorine atoms. Each bond uses 2 electrons, so 5 bonds use 10 electrons.
4. Subtract the bonding electrons from the total valence electrons to find the remaining electrons: 42 - 10 = 32 electrons. These remaining electrons are placed as lone pairs to satisfy the octet rule for the chlorine atoms first, then any leftover electrons are placed on the iodine atom.
5. Since iodine is in period 5, it can have an expanded octet. After placing lone pairs on the chlorines, the leftover electrons will form one lone pair on iodine, resulting in iodine being surrounded by five chlorine atoms and one lone pair.