Periodic Table and Atomic Structure

1. Valence Electrons: The outermost electrons of an atom; these determine the atom's characteristics, chemical properties, and bonding ability.

B. Similar elements are grouped together.

• Ordered based on the number of protons.

• Periods: Horizontal rows in the table.

  • The electron number increases as you move from left to right.

  • Electron arrangement becomes more complex as you move to the right and downward.

• Group: A vertical column of elements in the periodic table.

  • Atoms of elements in the same group have the same number of valence electrons and, therefore, have similar properties.

B. Ionization: Atoms that do not have a full outer s or p orbital can undergo this process.
C. Ion: An atom that has lost or gained one or more electrons, resulting in a net positive or negative charge.

A. Atomic Number: Equals the number of protons in the atom.

C. Atomic Mass: Equals the total number of protons and neutrons (the subatomic particles within the nucleus).B. Isotopes: Atoms of the same element that have the same number of protons but different numbers of neutrons, leading to variations in atomic mass.

1. amu: the unit of mass that describes the mass of atoms Bottom of Quiz

• A chart will be set up similar to the example provided below.

Symbol example: Gallium (Ga) 38.7, Yttrium (Y) 39