SOME COMMON SALTS AND THEIR USES
  Salt Name              Chemical name and                              Used to
                         formula
  Bleaching              Calcium hypochlorite     bleaching cotton and linen, bleaching wood
  powder                 (CaOCl2)                 pulp in paper factories, oxidising agent in
                                                  many chemical industries; and for disinfecting
                                                  drinking water to make it free of germs.
  Washing soda           Sodium Carbonate         manufacture of glass, chemicals such as
                         (Na2CO3)                 sodium silicates and sodium phosphates,
                                                  manufacture of detergents and as an alkaline
                                                  agent in many chemical industries.
  Baking soda            Sodium bicarbonate       ingredient in antacids, fire extinguishers, cake-
                          (NaHCO3)                making.
  Plaster                Calcium sulfate          plaster factures bones, for making toys, for
  of Paris               (CaSO4.1/2 H2O)          making smooth surface and various materials
                                                  for decoration. It was named plaster of Paris
                                                  because a large deposit of gypsum was found
                                                  in Montmartre in Paris.
  Copper sulfate         CuS04.5H20               combines sulfur with copper, kill bacteria,
                                                  algae, roots, plants, snails, and fungi.
  Quick lime             Calcium Oxide            making porcelain and glass; purifying sugar;
                         (CaO)                    preparing bleaching powder, calcium carbide,
                                                  and calcium cyanamide; in water softeners; and
                                                  in mortars and cements.
  Potassium              KNO3                     fertilizer in vegetable. food preservatives,
  Nitrate                                         explosive (gun powder), etc.
                       CLASSIFICATION OF ELEMENTS
Periodic Table                                        Mendeleev’s Periodic Table
  It is a tabular arrangement of the chemical
   elements, ordered by their atomic number
   (number        of      protons),    electron
   configurations, and recurring chemical
   properties.                                            Dmitri Ivanovich Mendeleev, a Russian
  The horizontal rows of the table are called             scientist arranged the elements in
   periods; the vertical columns are called                increasing order of their relative atomic
   groups.                                                 masses.
  Dmitri Mendeleev is generally credited                 Mendeleev’s Periodic Law states that the
   with the invention of the periodic table.               properties of elements are the periodic
                                                           function of their relative atomic masses.
                                                          Mendeleev arranged all 63 elements in a
                                                           tabular form. It is known as Mendeleev’s
                                                           Periodic Table.
                                                          It contains eight vertical columns of
                                                           elements called "groups" and seven
                                                           horizontal rows called "periods", Each
                                                           group has two sub-groups A and B.
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