chem 🧪

• Jons Jakob Berzelin


  A swedish chemist who developed a table of atomic weights and introduced letters to symbolize elements in 1828
• Johann Dobereiner


  One of the first chemist that groups of elements with similar properties exist
• Dobereiner's Law of triad


  When elements are arranged in order of increasing atomic weight, groups of three, having similar chemical properties are attained
• John Newlands


  Devised the first periodic table
• Law of octaves


  If elements were arranged in increasing atomic weight, similar properties would repeat every eight element
• Julius Lothar Meyer and Dmitri Jvahovich Mendeleev


  Credited for the discovery of the periodic law
• The periodic law


  If elements were arrange din increasing atomic weights, elements with similar properties would repeat periodically
• Mendeleev


  The father of the modern periodic table
• Henry Mosely


  Restated the periodic law
• Periods


  7 horizontal rows which are numbered consecutively from 1 to 7 in the periodic table
• Groups or families


  18 vertical columns which are numbered consecutively from 1 to 18 as recommended by IUPAC
• Alkali metals


  Groups 1 except for Hydrogen (H)
• Alkali earth metals


  Group 2
• Chalcogens


  Group 16
• Halogens


  Group 17
• Noble gases


  Group 18
• Groups 1, 2 and 13 to 18


  Representative elements
• S block


  Groups 1 to 12
• P blocks


  Groups 13 to 18
• D blocks


  Group 3 to 12
• F blocks


  Inner transition metals
• Alkali earth metals

  Very reactive, very soft, lustrous metals and forms compounds with halogens that are similar to table salt
• Halogens


  Forms compounds with alkali similar to table salt, outermost shell only needs one more electron since it is readily to accept and very reactive
• Noble gases


  Stable because of complete octet and unreactive
• Metallic elements


  High thermal and electrical conductivity
• Non metallic elements


  Doesn't conduct heat and electricity, little luster seldom reflect light, brittle and gains electrons
• Sodium Hydroxide


  Used to make soap, detergent, paper l, textiles and crayons
• Sodium Benzoate


  Low cost preservatives in foods and drinks
• Potassium Chlorate


  Oxygen in labs
• Cesium Bromide and Cesium Iodided


  Used in flourescent screens
• Magnesium hydroxide


  Ingridient of antacids
• Calsium Oxide


  Used in the steel industry
• Strontium


  Produces bright red flame and are used in signal flares and fireworks
• Titanium, chromium and zinc


  Corrosion resistant construction material
• Amalgams


  Alloys mercury forms
• Terbium

  used in tv screens to make green lights
• Neodymium

  Used in lasers
• Promethium

  An electrical power source for artifical hearts and pace makers
• Uranium and plutonium

  Used as raw materials in the production of nuclear energy
• aluminum

  Corrosion resistant, light, soft, easy to cut and a good conductor of electricity and heat