1. Deposit inhibitor
   1. Mechanism
      1. Threshold inhibition
      2. Crystal modification
      3. Sequestration
      4. Dispersion
   2. Types
      1. Polymers
         1. Silica
            1. Acrylic acid+Allyl hydroxy-propyl sulfonate ether
            2. Surfactants
            3. Borate
      2. Subtopic 2
2. Scale Inhibitor
   1. Threshold inhibition
   2. Crystal modification
   3. Sequestrants
3. Corrosion inhibitors
   1. Anodic
      1. Mechanism by interfering with anodic reaction
      2. Oxidising
         1. Mechanism
            1. promotes rapid oxidation of the metal surface
            2. they DO NOT require oxygen in order to function
            3. need minimum amount or else surface can loose protective layer and pitting with occur
            4. promote gamma iron oxide to form FeOOH
         2. Nitrites
      3. Non-oxidising
         1. Mechanism
            1. require the presence of oxygen
            2. form salts of iron to ppte onto the surface
            3. chemisorb onto the oxide layer reducing ion permeability
         2. Iron salts of carbonate
         3. Ortbophospphates
         4. Molybdates
         5. Phosphonates
   2. Cathodic
      1. Mechanism by preventing reduction of oxygen or electron transfer at the cathode
      2. Zinc based inhibitors
      3. Polyphosphate
      4. Carbonate
      5. Cathodic barrier films need physical and electrical impermeability to prevent oxygen from physically reaching the metal surface. Both are needed to prevent oxygen reduction.
      6. Cathodic barrier films are catalysed by hydroxide produced by the cathodic reaction
      7. Localised high pH also cause ppte of hydroxides to form inhibitor film
   3. Bipolar Films
      1. Mechanism combination of both anodic and cathodic
      2. Azoles
      3. Phosphonates
         1. PSO
         2. HEDP
         3. AMP
         4. PBTC
      4. Organic filming amines
   4. Film Forming
      1. Azoles
      2. Thiazoles