Physical Properties : Calcium hydroxide   is a colourless, crystalline , soft solid powder .It can also be found in its  granule form  . It is only slightly soluble in water and  so its solutions act as a weak base . It has an alkaline and a bitter taste . A saturated water solution of calcium hydroxide is known as lime water. It is a strong base and is widely used as an inexpensive alkali . 
 

Chemcial Properties : It  is obtained when  calcium oxide  is slaked  with water  . When heated above 580°C it dehydrates to form oxide again . Because calcium hydroxide readily reacts with carbon di oxide to form calcium carbonate, the presence  of carbondioxide in a mixture of gases can be detected by shaking it with limewater in a clear container  . Its presence will be known if a  cloudy precipitate of calcium carbonate forms .

Synonyms  : Slaked lime , Calcium hydrate , Hydrated lime , Carboxide , Calcium dihydroxide and Lime water .

Formula  : CA (OH)2  

Uses : Calcium hydroxide is mixed with water or other mediums to be used as a base material in cavity liners , pulp capping , concretes , agricultures, insecticides , glasses , petrochemicals and for the preparation of dry mixes for painting and decorating materials. It is also used as a filler in the manufacture of brake pads  and ebonite . It act as a bonding agent in motars , plasters , asphalt paving , insulation materials and  road soil stabilisation .It is used extensively in a very strong PH solution.Calcium hydroxide  is much in demand when a very rapid change in the PH value is required  .  It also finds its place in  reducing  the soil acidity and  in sugar refining . It helps a lot too, in the formation of calcium compounds . Lime water , a saturated solution of calcium hydroxide , is used in medicine to treat acid burns and as an antacid too . Being a strong base , it also finds its application in the petroleum refining industry.