C3.1 The Periodic Table

HideShow resource information
  • Created by: lilyb1509
  • Created on: 07-04-15 18:45
View mindmap
  • C3.1 The Periodic Table
    • 1863 -Newlands Law of Octaves
      • Similar properties repeated every eighth element
      • 62 elements known into seven groups according to atomic weight
      • Properties did not match well within groups
        • Scientists did not accept his ideas
    • 1869 - Mendeleev's Periodic Table
      • Gaps left for undiscovered elements
      • Groups of known elements had similar properties
      • Predicted properties of missing elements
        • Confirmed predictions meant scientists readily accepted his ideas
          • His table the basis for modern periodic table
    • Modern Periodic Table
      • The atomic number determines  position in the periodic table
      • Number of electrons in outer shell determines chemical properties
      • Group number = number of electrons in outer shell
      • Going down a group, there are more occupied energy levels = larger atoms
        • Electrons in outer shell are less strongly attracted by nucleus
    • Group One Metals
      • Alkali metals
      • React readily with air and water
        • Reacting with water produces hydrogen gas + metal hydroxide
          • sodium + water > sodium hydroxide + hydrogen
      • They lose their outer electron in reactions to form ionic compounds with a +1 charge
      • Reactivity increases going down the group
    • Between Groups 2 and 3
      • Transition elements / metals (all metals)
      • Higher melting and boiling points than alkali metals
        • Stronger, harder (good for building materials)  and good conductors of heat and electricity
      • React slowly, or not at all, with oxygen and water
      • Form positive ions with various charges
      • Important industrial catalysts
    • Group 7
      • The Halogens
        • Non-metallic
      • Low melting and boiling points increase going down group
      • Reactivity decreases going down group
      • They form ions with a single negative charge

Comments

No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all The Periodic Table resources »