Honors Chemistry Unit 3: Periodic Trends

Flashcards covering key concepts on periodic trends including valence electrons, atomic radius, effective nuclear charge, electron shielding, ionic radius, ionization energy, and electronegativity.

Valence electrons are the outermost electrons, involved in bonding, and give the elements their __.

properties

Atomic radius is the size or radius of an atom, measured from the center to the __.

outermost electron

The biggest atom on the periodic table is and the smallest atom is .

Fr, He

Atomic radius generally across a period from left to right and generally down a group.

decreases, increases

__ is the increasing pull of protons on electrons as the number of protons increases, only for the trend from left to right.

Effective nuclear charge

__ occurs when outer electrons do not feel the full pull of the nucleus because other electrons are in the way, primarily affecting the trend down a group.

Electron shielding

If an atom gains an electron, its ionic radius will __, and if it loses an electron, its ionic radius will __.

increase, decrease

__ is defined as the energy required to remove an electron from a gaseous atom.

Ionization energy

Noble gases have really __ ionization energy.

high

First ionization energy from left to right across a period and down a group.

increases, decreases

__ indicates an element's relative ability to attract electrons in a chemical bond.

Electronegativity

Electronegativity down a group and from left to right across a period.

decreases, increases

The element with the highest electronegativity, wanting an electron really badly, is __.

Fluorine (F)

__ are generally not included in the electronegativity trend because they typically do not attract electrons in a chemical bond.

Noble gases