2.3 Properties of Atoms

Understand that in neutral atoms proton number equals electron numbers and that the number of valence electrons determines reactivity, including energy levels.

Study Guide

Explain each Concept

è The four forces at work in an atom are:

è In the current atomic theory, electron clouds are where electrons:

è Chemical bonding is the joining of atoms to form new substances.

è A chemical bond is a force of attraction that holds two atoms together.

è Valence electrons are the electrons in the outermost energy level of an atom.

è Valence electrons are used to form bonds.

è Most atoms form bonds by gaining, losing, or sharing electrons.

è The valence has room for 8 valence electrons.

è Atoms of hydrogen, lithium, and helium need only 2 electrons to fill the valence .

è Electron-dot diagrams are a simple way to represent the valence electrons in an atom.