Wednesday, September 28, 2011

Chemistry Form 4: Chapter 7 - Neutralization Reaction

As you can see from the equations, acids release H+ into solution and bases release OH-. If we were to mix an acid and base together, the H+ ion would combine with the OH- ion to make the molecule H2O, or plain water:

H+(aq) +   OH-(aq)  arrow H2O
Neutralization is a reaction between acid and base to produce salt and water only as shown below:

HCl  +  NaOH  arrow H2O  +  NaCl
HBr  +  KOH  arrow H2O  +  KBr

Uses of neutralization
  1. Soil treatment - if the soil is too acidic, it is treated with a base in order to neutralise it. Common treatments use quicklime (calcium oxide) or chalk (calcium carbonate). 
  2. Indigestion -  too much hydrochloric acid in our stomach leads to indigestion. Therefore, to cure this ailment we need to neutralise the acid with a base such as, sodium hydrogen carbonate (baking soda), or milk of magnesia. 
  3. Bee sting contains acid -  In order to relieve the painful symptoms of the sting we need to neutralise the acid. By rubbing on calamine lotion (zinc carbonate) or baking soda the acid can be neutralised.
  4. Wasp sting contains alkaline -  Hence acid is needed to neutralise and remove the painful sting. Vinegar (ethanoic acid) is used.

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