Acids, Bases and pH Scales

What is an acid and a base?
The first person that tried to define acids and bases was Arrhenius. His theory proposed that an acid is any substance that produces a proton H+, when dissolved in water and the resulting solution is an electrolyte. A base is any substance that produces hydroxide ions, when dissolved in water; they are also called alkali. This theory was able to explain the way acids and bases react; the only substance that the theory was not able to explain was NH3. So the definition of an acid and a base was redefined, and the Brønsted-Lowry Theory was created.…