Periodic Trends

• The periodic table is governed by PERIODIC LAW
• Periodic Law - is considered to be one of the most important concepts in chemistry. It helps chemists to predict how an element will behave
• Characteristics of metal

  1. Solid at room temperature are (except for mercury [Hg), which is a liquid at room temperature
  2. Ductile
  3. Lustrous
  4. Good conductors of heat and electricity
  5. Malleable
  6. Prone to lose electrons easily
• Characteristics of non-metals

  1. Brittle
  2. Dull or not shiny
  3. Poor conductors of electricity and heat
  4. Solid, liquid, or gaseous at room temperature
  5. Able to gain or share electrons easily
• Non-metals - have properties that are opposite from those metals
• Metalloids - have properties that are a mix of metal and nonmetal properties
• Characteristics of metalloids

  1. Solid at room temperature
  2. Dull or shiny
  3. A mix of good conductors and poor conductors of electricity and heat
  4. Characterized by having physical properties that tend to be metallic and chemical properties that tend to be nonmetallic
• Valence electron - an electron located at the outermost shell
• Valence electrons decide how an atom will react in a chemical reaction
• Every element wants to have a FULL OCTET
• Full octet - typically, but not always, eight electrons in the outer shell
• To get a full octet, an element will gain or lose valence electron
• Octet rule - a rule that states that elements must combine in such a way that each atom has eight electrons in its valence shell, so that it has the same electronic configuration as a noble gas