When iodine forms its most common ion, represented as I^-, how many protons and electrons does it have?

• A. 53 protons and 53 electrons
• B. 54 protons and 53 electrons
• C. 54 protons and 54 electrons
• D. 53 protons and 54 electrons

Answer: (D)

Verified step by step guidance

1. Identify the atomic number of iodine (I), which tells us the number of protons. Iodine has an atomic number of 53, so it has 53 protons.
2. Understand that the number of protons in an element does not change when it forms ions; only the number of electrons changes.
3. Recognize that the ion I^- indicates that iodine has gained one extra electron compared to its neutral state.
4. Since a neutral iodine atom has 53 electrons (equal to the number of protons), the I^- ion will have one more electron, totaling 54 electrons.
5. Conclude that the I^- ion has 53 protons and 54 electrons.