THEORY OF ACIDS-BASES

THEORY OF ACIDS-BASES

Acid-Base

Acids and bases are two classes of chemicals that are very important in everyday life. In connection with the acidic nature of Basa, a solution grouped into three categories, namely acidic, alkaline, and neutral. Acids and bases have different properties, so can we can determine the nature of a solution. To determine a solution is acidic or alkaline, there are several ways. The first uses a color indicator, which will indicate the nature of a solution with a color change occurs. Litmus instance, turns red in acidic solution and will be colored blue in the solution is alkaline. Acid-base properties of a solution can also be determined by measuring its pH. pHmerupakan a parameter used to express the acidity of the solution. Acid solution has a pH less than 7, the base solution has a pH greater than 7, while the neutral solution has a pH = 7. pH of a solution can be determined with a pH indicator or pH meter.


Arrhenius Acid-Base Theory

Since many centuries ago, chemists define acids and bases based on the nature of the solution. Acid solution has a sour taste and is corrosive (harmful metals, marble, and various other materials). while bases taste is somewhat bitter and caustic (slippery). But there are some opinions that explain the cause of the nature of acids and bases. In 1777, Antoine Laurent Lavoisier (1743-1794) suggested that oxygen-containing acid. Davy later concluded that the element hidrogenlah that the basic constituents of acid. Then in 1814 Joseph Louis Gay-Lussac (1778-1850) concluded that the acid is a substance that can neutralize the alkali and the second class of compounds that can only be defined in relation to one another. But the concept / opinion quite satisfactory, and acceptable until recently advanced by Svante August Arrhenius (1859-1927), namely:



Acid 
acid is a substance that in water releasing H + ions. in other words, the carrier is acidic nature of H + ions. and formulated with

HxZ (aq )---------» XH + (aq) + ZX-(aq)

Base
base is a substance in water produces hydroxide ions (OH-). in other words, the carrier is the alkalinity (OH-). and formulated with
M (OH) x (aq )---------» Mx + (aq) + xOH-(aq)