Question

Write the name and chemical formula of bases present in milk of magnesia.

Answer 1

Milk of magnesia is an inorganic compound it is called milk of magnesia because of its milky appearance and it is of white colour. Chemical name of milk of magnesia is Magnesium Dihydroxide or Magnesium Hydroxide. It is prepared by treating magnesium salts with alkaline water which gives magnesium oxide as precipitate.

Complete answer:
Milk of magnesia is prepared by treating magnesium salts with alkaline water which gives magnesium oxide as precipitate. This method is used for producing a small amount of milk of magnesia. The reaction takes place is given as
$M{g^{2 + }} + O{H^ - } \to Mg{\left( {OH} \right)_2}$
The above reaction is in ionic form, Magnesium cation reacts with Hydroxyl ion to give Magnesium di hydroxide or milk of magnesia.
Milk of magnesia occurs in nature in the form of a mineral brucite. It does not have odour, it is white in colour. The melting point of Magnesium Hydroxide is approximately $350\;^\circ C$ . It is not very soluble in water and has a solubility product, ${K_{sp}} = 5.6 \times {10^{ - 12}}$ .
Let’s see what are the usage of milk of magnesia
-It is used in various types of medications, it is used as an antacid, it is used as a laxative.
-It is used as fire resistant as the natural brucite form of milk of magnesia is a fire retardant.
-It is used to produce magnesia which is good thermal conductor
-It is used in antiperspirant which prevents sweat and odour.

Note:
This method is not used for large scale production of milk of magnesia for production at commercial scale sea water is treated to the Calcium Hydroxide or lime soda to produce large amounts of milk of magnesia.