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					- a summary
of actions
and cautions
Cleaning Product Families

                                 Detergents
          Solvents




                     Household
  Acids              Cleaning                 Soaps
                      Agents



            Bases                       Abrasives

                     Bleaches
        Acid cleaners:
        • can be used to remove
Acids     tarnish, alkaline staining and
          rust from metals, hard water
          stains from many surfaces
        • will neutralise bases or
          alkalis
        • may have bleaching
          effects
        Caution: Acids can:
        • damage eyes, skin, and
          fabrics
        • eat through metal
        • scratch surfaces and
          porcelain enamel
             Bases and Alkalis
• a base is the opposite of an acid:
   - the effect of an acid is to increase the hydronium
  ion (H3O+) concentration in water
   - the effect of a base is to reduce H3O+
  concentration
• bases react with acids to produce water and salts (or
  their solutions) – this type of reaction is called
  neutralisation
• a base which is dissolved in water is called an alkali
• alkali cleaners get rid of and postpone heavy soil and
  grease so it can be rinsed away
Caution:
• alkalis can harm skin and fabrics, corrode and darken
  aluminium
• most alkalis (except baking soda) are poisonous if
  swallowed
Bleaches   Bleaches:
           • can oxidize and
             remove stains from
             surfaces and fabrics
           • may be used to
             reduce stains in wood
             as well as remove the
             colour naturally in
             woods such as
             mahogany
           Caution: clean bleach
             thoroughly and
             promptly to prevent
             fading
                             Soaps
Soaps
• anionic surfactants used in conjunction with water for
  washing and cleaning
• come as solid bars or as viscous liquids
• consist of sodium or potassium salts of fatty acids
• obtained by reacting common oils or fats with a strong
  alkaline solution (the base, popularly referred to as lye)
  in a process known as saponification
  - the fats are hydrolysed by the base, yielding alkali salts of fatty
  acids (crude soap) and glycerol
• today, soap is often replaced by other cleaning agents,
  such as synthetic detergents
             Detergents

Detergents   • can be alkaline/basic (pH > 7) or
               neutral (pH = 7)
                - neutral detergents are pH 7
               meaning neither acidic nor alkaline
                - read the can or bottle to determine
               how alkaline the detergent is
             • mild detergents have surfactants that
               dissolve dirt and grease
             • strong detergents have both a
               surfactant and a builder, so dissolves
               heavier soil and grease

             Caution: Most powdered detergents
               contain washing soda as a builder
               and some are very alkaline which
               can damage surfaces and irritate skin
               with prolonged contact. Strong
               solutions can dissolve paint. Always
               rinse thoroughly.
                             Solvents
Solvent cleaners are gladly available and are often used to dissolve
   household soil. The solvent is often the medium the stain or soil
   goes into to helping its removal.
Water:
• worldwide solvent because it will dissolve most kinds of soils
   except oils
• alkalis, acids, bleaches or detergents are added to water to
   chemically respond with specific soils and loosen them so they
   are removed with the water
• prompt sponging with water (if material is water safe) will remove
   many stains without adding chemicals

  Caution: Surfaces damaged by water include:
     - wood (which warps)
     - wood finishes (which soften or turn white)
     - textiles (which shrink)
     - padding (which can be soaked and will form mildew)
     - materials that soften or disintegrate in water (such as paper)
     - electrical components (which may cause electrical shock hazards)
                      Abrasives
Abrasive cleaners are mechanical cleaners. They:
• physically scratch off dirt, stains and tarnish by the
  friction caused as you rub the surface
• are composed of either particles or physical abraders
  such as sandpaper, steel wool or scrubbing pads
  - the finer the particle, the less abrasive e.g. baking soda
  - the coarser the particle, the more abrasive e.g. salt
• change both the reflection from, and texture of,
  surfaces e.g. they dull glossy surfaces

 Caution: should never be used on mica because they
 take away top layers making future cleaning eventually
 impossible
       Cleaning Products Table
  Product     Type of       Chemical                pH –             pH –
              cleaner       compound            litmus test       pH meter
                                                                   reading
cloudy       Alkali          ammonia,         Red litmus paper
                                                                   11.9
                                              turns blue
ammonia                        NH3            Blue litmus paper
                                              stays blue

dishwashing detergent     anionic and non-    Red litmus paper
                                                                    7.0
                          ionic surfactants   stays red
liquid                                        Blue litmus paper
                                              stays blue

white        acid          acetic acid,       Blue litmus paper
                                                                    2.9
                                              turns red
vinegar                     CH3COOH           Red litmus paper
                                              stays red

toothpaste   abrasives   calcium phosphate,   Red litmus paper
                                                                    9.9
                         Ca3(PO4)2            turns blue
                         alumina, Al2O3       Blue litmus paper
                         calcium carbonate,   stays blue
                         CaCO3

				
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