Chemistry Unit 5

Nuclear Charge

The total charge of all protons in the nucleus. It determines the attractive force experienced by electrons.

Shielding

The reduction of the effective nuclear charge experienced by an electron due to the presence of other electrons. Core electrons shield valence electrons more effectively.

Atomic Radius

A measure of the size of an atom, typically defined as half the distance between the nuclei of two identical atoms bonded together. Increases down a group and decreases across a period.

Ionization Energy

The energy required to remove an electron from a gaseous atom or ion. Increases across a period and decreases down a group.

Electronegativity

A measure of the ability of an atom in a chemical compound to attract electrons. Increases across a period and decreases down a group.

Reactivity

The tendency of a substance to undergo chemical reactions. For metals, reactivity increases down a group and decreases across a period. For nonmetals, reactivity generally decreases down a group and increases across a period.

AIMES Chart

A periodic table based chart to summarize periodic trends in Atomic Radius, Ionization Energy, Metallic Character, Electronegativity and Shielding.

Valence Electrons

The electrons in the outermost shell of an atom that participate in chemical bonding. Determine the chemical