C1 - Atomic Structure & The Periodic Table

C1 - Atomic Structure & The Periodic Table

1. Structure of the Atom

   • Mass
     • Proton = 1
     • Neutron = 1
     • Electron - very small
   • Charge
     • Proton = 1+
     • Electron = 1-
     • Neutron = 0
   • Structure
     • Protons and neutrons in the tiny nucleus at the centre
     • Electrons in shells around the nucleus
       • 2 in 1st shell, 8 in 2nd shell, 8 in 3rd shell
       • electrons drawn in NESW, then double up!
   • Isotopes
     • Same number of protons, different number of neutrons
       • Relative Atomic Mass (RAM)
         • (mass of 1st isotope x abundance) + (mass of 2nd isotope x abundance) / 100

2. The Periodic Table

   • Newlands
     • arranged elements in order of atomic mass
       • Noted similar chemical reactivity in every 8th element
         • BUT mixed metals and non metals and had two elements in one space
   • Mendeleev
     • Arranged the elements in order of mass
       • Realised that some elements did not fit the pattern of reactivity
         • he left gaps for elements that had not yet been discovered
           • Later, elements were discovered that fit the gaps
   • Groups
     • Group 1
       • Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Caesium (Cs)
       • The reactivity XXcreases as you go _____ the group
       • The Alkali Metals
         • Stored in oil because they react with oxygen and water very quickly
         • Reaction with water
           • Lithium
             • fizzed, crimson red flame
           • Sodium
             • fizzed, melted, yellow-orange flame
           • Potassium
             • fizzed, caught fire, exploded! lilac flame
     • Group 7
       • The Halogens
         • Chlorine
           • A green gas
         • The reactivity XXcreases as you go _____ the group
         • Fluorine (F)
         • Bromine
           • An orange brown liquid
         • Fluorine
           • A pale yellow gas
         • Iodine
           • A grey solid (and a purple gas)
     • Group 0
       • Very unreactive because they have a full outer shell of electrons
       • Density XXcreases as you go _____ the group
       • Size of atom XXcreases as you go _____ the group
     • Columns
   • Metals and Non-metals
     • Metals to the left of the staircase line, non-metals to the right

3. Separating Mixtures

   • Filtration
     • Separates an insoluble solid from a liquid
       • Equipment
         • Funnel, Filter paper, conical flask
     • Residue
       • the solid left in the filter paper
     • Filtrate
       • the liquid that passes through the filter paper
   • Crystallisation
     • Separates a soluble solid from a liquid
       • Equipment
         • Evaporating basin, an electric heater
     • Evaporation
       • the liquid turns to a gas and leaves crystals of the solid behind
   • Chromatography
     • Separates inks & food colours
     • Stationary phase
       • Paper
     • Mobile phase
       • Solvent ( Water )
     • Rf value
       • height of spot / height of solvent front
   • Distillation
     • Separates two liquids with different Boiling Points
     • Equipment
       • Round bottomed flask, heat, condenser, beaker
     • Evaporation of one liquid happens in the round bottomed flask.
       • The vapour condenses in the condenser and collects in the beaker
         • The other liquid doesn't evaporate and stays in the round bottomed flask