BASE

• BASES are substances that accept or react with H+ions.
• A drop of a base solution changes a red litmus paper to blue. Phenolphthalein becomes red from colorless in base solution.
• PROPERTIES OF BASES

  1.) Bases furnish hydroxyl ions (OH- ) in solution.

  2.) Strong solutions of bases are caustic and have a slippery feel.

  3.) Base solutions of active metals saponify fats.

  4.) Bases react with the oxides of non-metals to form salt and sometimes water.
• The hydroxyl ions which are present in basic solutions could be used as a precipitant in removing or reducing water’s most troublesome impurity known as water hardness.
• WATER HARDNESS is caused by the dissolved salts of calcium and magnesium present in water.
• STRONG BASES give a relatively high concentration of hydroxide ions because they dissociate completely or nearly so in solutions. NaOH and KOH are strong bases.
• WEAK BASES give a relatively low concentration of hydroxide ions because they are slightly dissociated in solutions. NH4OH is an example of a weak base.
• Very soluble bases are soapy and have a slippery feel when rubbed between the thumb and forefinger.
• A base solution, when saponifying a fat breaks a long chain of hydrocarbons to form a metallic salt and an alcohol.
• Sodium hydroxide is used to hydrolyze the glyceryl stearate in the presence of heat to form a metallic salt, sodium stearate and glycerin.
• The metallic salt, sodium stearate formed in the saponification reaction is commonly known as soap
• “AIR-SEPARATION PROCESS”

  Before air is subjected to high pressure compression, it is stripped off of its carbon dioxide content by reaction with potassium hydroxide solution (scrubber). The KOH solution is passed counter current to the upward flow of air.