Acids and Bases

Acids and bases have been known very well for their properties since the early days of experimental chemistry. The word "acid" comes from the Latin word acidus, meaning "sour" or "tart," since water solutions of acids have a sour or tart taste. A good example of an Acid is vinegar. Vinegar has a 5 percent water solution of acetic acid. reaction_acidbase3.gifBesides having a sour taste, acids react with active metals to give hydrogen, they change the colors of the indicators (for example, litmus turns from blue to red), and they neutralize bases. Bases can change the colors of indicators too (litmus turns from red to blue) and they can neutralize acids. Hence, bases are considered the chemical opposite of acids. ph-scale.pngAcids and Bases are also known for the measurements of ions in liquids. Almost every liquid you see has ions in it. To see just how much Ions are in the liquid scientists use something called Ph Scale. The pH scale ranges from 0 to 14. A pH of 7 is neutral.reaction_acidbase4.gif A pH less than 7 is acidic. A pH greater than 7 is basic.
The picture below shows an example of Ph scale. An acidic liquid is any liquid that produces a lot of hydrogen ions. These ions symbol is H+. A Basic liquid is any liquid that has a lot of hydroxide ions and that symbol is OH-. Strong Acids have a very low Ph level. And Strong Bases have very high Ph level.







The Neutralization Equation



Acid + Base = Water + Salt

Heres an example:

NaOH+HClNaCl+H2O