Caustic Soda or Sodium Hydroxide has many different uses such as unblocking drains and making soap. Caustic soda main uses include being used as a drain pipe cleaner, unblocks drains, removes built up grease from ovens, used to make soap and detergents. It is used as a cleansing agent and in the manufacturing of washing soda. Sometimes, sodium hydroxide is also used as a reagent in the laboratories. It is used in the preparation of soda lime. It is used in the extraction of aluminium by purifying bauxite.