C4 REVISION COMPLETED

Created by: Irammm
Created on: 25-05-13 15:21

View mindmap

C4 REVSION
- Metals & Water
  - Metals have a high melting point due to their strong metallic bonding
  - Cu2+ ions react with sodium hydroxide to make blue solid in a precipitation reaction
  - Superconductors conduct electricity with little or no resistance
  - The thermal decomposition of transition metal carbonates results in the metal oxide & carbon oxide being made
  - Drinking water is purified by filtration, sedimentation and chlorination
  - Copper compounds are often blue, iron(||) compounds are light green & iron(|||) compounds are often orange/brown
  - Sulfates in water can be tested using barium chloride, halides can be tested using silver nitrate
- Atomic structure & atomic bonding
  - Ionic bonding happens because of the transfer of electrons from metals to non metals
  - The nucleus is made up protons & neutrons, it is surrounded by electrons
  - Isotopes are elements that have the same atomic number but different mass numbers
  - Electron=negetive charge, Protons= positive charge & neutrons= no charge
  - Sodium Chloride & Magnesium oxide form giant ionic lattices as their ions attract each other
  - Metals form positive ions as they loose electrons
  - 'Dot & Cross' models can be used to represent the ionic bonding in compounds
  - Non metals form negative ions as they gain electrons
- Groups
  - To identify the presence of lithium, sodium & potassium, flame tests can be used.
  - Group 1 metals have similar properties as they all need to loose one electron from their outer shell.
  - Chlorine= green gas. Bromine= brown liquid & Iodine= is a grey solid
  - Rubidium & Caesium are Group 1 metals which react violently with water to give off hydrogen and make an alkaline solution
  - If a group 1 metal reacts with a group 7 non metal the word equation for the formation of a metal halide can be constructed
  - The group number is the same as the number of electrons in the outside shell.
- The Periodic Table & Covalent Bonding
  - Non metals combine by sharing electrons
  - The period to which an element belongs to is the same as the number of occupied electron shells
  - Carbon Dioxide & water have low melting points as the intermolecular forces between them are weak
  - Carbon Dioxide & water are simple molecules with weak intermolecular forces between the molecules