Identify the false statement about atomic and ionic radii. (LO 6.3) (a) I- has a larger radius than Br- (b) Ba2+ has a smaller radius than Ba (c) Te has a larger radius than Te2- (d) Sr2+ has a smaller radius than Se2-

The atomic radius is a measure of the size of an atom, typically defined as the distance from the nucleus to the outermost electron shell. Atomic radii generally increase down a group in the periodic table due to the addition of electron shells, while they decrease across a period due to increased nuclear charge, which pulls electrons closer to the nucleus.

The ionic radius refers to the size of an ion in a crystal lattice. Cations (positively charged ions) are smaller than their neutral atoms because they lose electrons, resulting in reduced electron-electron repulsion and a stronger pull from the nucleus. Conversely, anions (negatively charged ions) are larger than their neutral atoms due to the addition of electrons, which increases repulsion among electrons.

Understanding the trends in ionic and atomic radii is crucial for comparing different elements and their ions. Generally, as you move down a group, both atomic and ionic radii increase, while moving across a period results in a decrease in atomic radius and a more complex pattern for ionic radii, influenced by the charge of the ions. This knowledge helps in evaluating statements about the relative sizes of different ions and atoms.