Acids, Bases & Salts

Acids, Bases & Salts

1. Acids

   • A SUBSTANCE THAT BREAKS APART TO PRODUCE HYDROGEN IONS (H+)
     • HCl & HNO3
       • Monobasic: Produce 1 Hydrogen ion
       • Mineral Acids/Strong Acid
       • HNO3: Used in fertilisers and explosives
     • H2SO4
       • Dibasic: Produce 2 Hydrogen ions
       • Used in Car Batteries, detergents, fibres and pigments
   • Properties
     • Conducts Electricity
     • pH= < 7
     • Corrosive
     • Neutralises Bases and Alkalis
     • Weak Acids taste Sour

2. Alkalis & Bases

   • Alkali: Soluble Base
     • Strong Alkali: Completely Ionised
       • NaOH
         • Used in soap and oven cleaner
       • KOH
       • pH = 11-14
     • Weak Alkali: Partially Ionised
       • NH3
         • pH = 8-11
         • Used in fertilisers nitric acid and nylon
     • Properties
       • Conducts Electricity
       • pH = > 7
       • Corrosive Liquids
       • Neutralise Acids
       • Weak Alkalis feel soapy
   • Base: Substance that reacts to form Salt and Water only

3. Indicators

   • Litmus Paper
     • Red
       • In Acid: Red
       • In neutral: Red
       • In acid: Blue
     • Blue
       • In Acid: Red
       • In neutral: Blue
       • In Alkali: Blue
   • Phenolphthalein
     • In Acid: Colourless
     • In Alkalis: Pink
   • Methyl Orange
     • In Acid: Red
     • In Alkali: Yellow
   • Universal Indicator
     • Strong Acid/Dilute Hydrochloric Acid: 0-2
     • Weak Acid/Ethanoic Acid: 3-4
     • Weak Acid/Rain Water: 5-6
     • Neutral/Water or Sodium Chloride: 7
     • Weak Alkali: 8-9
     • Weak Alkali/Ammonia: 10-11
     • Strong Alkali/Sodium Carbonate or Sodium Hydroxide: 12-14

4. Neutralisation

   • H+ + OH- = H20
   • Occurs when H+ ions react with OH- ions to form water