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Chemistry - Coggle Diagram

- - - - Acid - Red
      - Alkali - Blue
    - - Acid - Colourless
      - Alkali - Pink
    - - Acid - Red
      - Alkali - Yellow
  - - - Alkalis are soluble bases and are a source of hydroxide ions, OH-, in water:
      - NaOH(aq) → Na+
      - (aq) + OH−
      - (aq)
  - - - metal + acid → salt + hydrogen
        
        Metal Observation with dilute acid (H2SO4 or HCl)
        
        magnesium vigorous effervescence, metal disappears, mixture warms
        
        aluminium slow but on warming; vigorous effervescence.
        
        metal disappears, mixture warms
        
        zinc slow effervescence when cold but more rapid on warming
        
        iron slow effervescence when cold but more rapid on warming
- - - - Properties of Ionic Compounds
        
        have high melting/boiling point due to many strong electrostatic
        attractions between oppositely charged ions
        
        melting/boiling points increase with increasing charge on ions – there
        is a stronger attraction between +2 and −2 charges than +1 and −1
        
        tend to be brittle – crystal distortion puts ions of the same charge next
        to each other – repulsion splits the crystal
        
        do not conduct electricity in solid form as ions cannot move
        
        do conduct electricity in solution or when molten as ions separate and
        are free to move
  - - - Simple Molecular
        
        lots of small molecules, held together by weak
        intermolecular forces
        
        The covalent bonds are incredibly strong and are not broken.
        
        there are weak forces of attraction between molecules – these are easily overcome and give simple molecular structures low melting/boiling points (typically gaseous at room temp)
      - Giant Covalent
        
        all atoms are covalently bound in a giant 3D structure
        
        all atoms are connected by many strong covalent bonds
        
        there are no delocalised electrons to conduct electricity
        
        all atoms are connected by many strong covalent bonds
        
        ‐ to melt the substance, the strong bonds must be broken – very high
        
        melting/boiling points