subject: Understanding Acids and Bases with Oranges, Lemons & Soap [print this page] Understanding Acids and Bases with Oranges, Lemons & Soap
Most people first learned of acids and bases in basic chemistry either in middle school or high school. Unless you are a chemist, a doctor or scientist, most people forget what acids and bases are the minute they get out of high school. Acids and bases are important substances in our daily lives so let's take the time to get re-acquainted with them.
? Where do acids and bases come from?
Water. The most abundant fluid on earth and definitely the most abundant substance in our body (accounts for 60-70% of the body weight expressed as the percentage of the lean body mass), water has the tendency to ionize or dissociate and can act as either an acid or a base.
H2O + H2O H3O+ (Acid) + OH- (base)
? How does an acid differ from a base?
Property Acids Bases
pH Less than 7 More than 7
Concentration of H+ High Low
Relationship to protons Donors Acceptors
Reaction to litmus paper Turns blue litmus paper to red Turns red litmus paper to blue
? What are common acids?
The most common and the most abundant acid, is the acid that our own body produces during metabolism- Carbon dioxide in the form of carbonic acid, which a normal adult produces about 28L/day. Other acids include-gastric acid, the acid found in our stomachs; sulfuric acid and hydrochloric acid found in most bathroom cleaners, ascorbic acid - our common vitamin C tablets, citric acid found in sodas, oranges and lemons, acetic acid which is vinegar.
? What are common bases?
The most popular base is sodium bicarbonate or what we know as baking soda. Bicarbonates are also found in our body which helps neutralize half of the acid that our body produces. Other bases are caustic soda - used in the manufacture of soaps, common over the counter antacids - aluminum magnesium hydroxide (Maalox, Tums), laxatives such as milk of magnesia are also example of bases.
Acids and bases are integral substances in our daily living; a disruption in the body's acid-base balance could bring about catastrophic even fatal outcomes if left unattended. Diabetics may succumb to excess acid in the body in what is known as diabetic ketoacidosis. Accidental ingestion of alkalis such as household cleaners could be fatal. So the next time you grab hold of an orange or drink lemon juice, keep in mind that it's an acid and the next time you use that bar of soap, you know that, that's a base.
