The Periodic Table

• Atomic number = the number of protons in an atom's nucleus.
• Protons have positive charges.
• Neutrons are neutral.
• Electrons have negative charges.
• Metals are sonorous , malleable , shiny , good conductors of heat and electricty and have high melting points.
• Non metals are bad conductors of heat and electricty, dull and brittle.
• metal + oxygen makes metal oxide
• In a displacement reaction a more reactive element is replaced by a les reactive element.
• metal + water

  metal hydroxide + hydrogen
• Group 1

  Lithium

  Sodium

  Potassium

  Rubidum

  Caesium

  Francium
• Group 7 are known as halogens.
• Group 0 are known as the noble gases.
• Physical Properties

  things you can observe and measure
• Chemical Properties

  They describe substances react
• Group 0 elements are unreactive
• Metalloids have the properties of metals and nonmetals
• The reactivity in group 1 increases as you go down the group.
• The reactivity in group 7 increases as you go up the group.
• Properties of group 1

  Low melting and boiling points , reactive , low density
• lithium + water

  lithium hydroxide + hydrogen
• Noble gases are found underground.
• Alkali metals are very reactive, soft and light.
• Noble gases do not form compounds with other elements.