An element with the smallest anionic (negative-ionic) radius would be found on the periodic table in which location?

• A. the bottom left corner (Group 1, Period 7)
• B. the center of the table (transition metals)
• C. the top right corner (Group 17, Period 2)
• D. the top left corner (Group 1, Period 2)

Answer: (C)

Verified step by step guidance

1. Understand that an anion is a negatively charged ion formed when an atom gains electrons, which generally increases its radius compared to the neutral atom due to increased electron-electron repulsion.
2. Recall the periodic trends for atomic and ionic radii: atomic and ionic sizes generally decrease from left to right across a period due to increasing nuclear charge pulling electrons closer, and increase from top to bottom within a group due to the addition of electron shells.
3. Recognize that for anions, the size is influenced by the number of electrons gained and the effective nuclear charge; smaller anions are found where the nuclear charge is high and the added electrons do not significantly increase electron-electron repulsion.
4. Identify that the top right corner of the periodic table (excluding noble gases) contains elements with high effective nuclear charge and relatively few electron shells, leading to smaller anionic radii; specifically, Group 17 (halogens) in Period 2 form small anions.
5. Conclude that the element with the smallest anionic radius would be located at the top right corner of the periodic table, such as fluorine in Group 17, Period 2.