Periodic Table and Naming Compounds Notes

Periodic Table

• Periods (1-7): Each horizontal line in the periodic table.
• Group or Family (1-18): Vertical columns that share similar chemical and physical properties.
• Alkali Metals: Group 1 elements. They are soft, shiny, silver-colored, and highly reactive with water.
• Alkaline Earth Metals: Group 2 elements. They are reactive but less soluble in water compared to alkali metals.
• Halogens: Group 17 elements. They are poisonous and highly reactive with alkali metals, forming salts.
• Noble Gases: They are stable (inert) elements.

Metals

• Good conductors of electricity and heat.
• Malleable (can be hammered into thin sheets).
• Ductile (can be drawn into wires).

Metalloids

• Have properties that are intermediate between metals and non-metals.

Non-Metals

• Grouped together due to the lack of similar properties to metals.

Atomic Number

• Indicates the number of protons in an atom.

Atomic Mass

• Number of protons + number of neutrons in an atom.

Isotopes

• Atoms of the same element that contain different numbers of neutrons.

Atomic Theory

• Energy Levels: Electrons occupy the majority of the volume of an atom and exist at specific energy levels.
• Energy levels closest to the nucleus have the lowest energy.
• Electrons and protons are attracted to each other due to opposite charges but cannot come together.

Atomic Theory - Ionization

• Atoms gain or lose electrons to achieve the electron configuration of the nearest noble gas.

• Atoms in most elements will gain or lose one or more of their outermost electrons, resulting in ions.

• Ionization results in the formation of compounds between metals and non-metals.

• Cation: Positively charged ions (lose electrons). Metals tend to lose electrons.

• Anion: Negatively charged ions (gain electrons). Non-metals tend to gain electrons.

  Example: Calcium (Ca)

  • $20 P$ (20 Protons)
  • $20 N$ (20Neutrons)
  • Electron Configuration: $1s^2 2s^2 2p^6 3s^2 3p^6 4s^2$

Valence Electrons

• The number of electrons in the outermost energy level (valence shell).
• Elements in the same group/family have the same number of valence electrons.