Sec 2 Chem: Acids and Bases (Introduction)

Commons acids in the Science lab include:

Hydrochloric Acid	HCl
Sulfuric Acid	H2SO4
Nitric Acids	HNO3

Note: Amino acids are not acids! Only acidic amino acids are!

A characteristic of acids is that they dissociate into H+ ions in water (Aqueous): For example:

HCl à H⁺ + Cl^-

H₂SO₄ à 2H⁺ + SO₄^2-

Note that dissociation ereactions are reversible, hence the àsign should be replaced by the following symbol, which cannot be types out on blogspot : 

It is the weird double-headed arrow in the centre...just ingore the A and B and S and T...dunno how to crop....

Strong acids are those that dissociate fully in water. Weak acids are those that partially dissociate. For example, ethanoic acid, CH₃COOH, dissociates in water to form CH₃COO^- and H⁺ ions. However, only 4% of the molecules dissociates.

The basicity of an acid is the number of H⁺ ions they dissociate in water. (Note: Ethanoic Acids has a basicity of 1 istead of 4, as the H₃ remains together when in water)

The scientist Svante Arrhenius proposed that acids dissociates in water to form H+ ions. Hence, a compound that exhibit this character is called an Arrhenius acid.

As for bases, here are some commons ones:

Sodium Hydroxide	NaOH
Calcium Hydroxide	Ca(OH)2

Arrhenius’ definition of a base is a compound that dissociates to form OH^- ions in water.

However, compounds such as Ammonia, NH₃ and Cooper Oxide, CuO, are regarded as bases too, despite not having an OH^- ion. Hence Arrhenius’ model went into some difficulties (See “Changing models of Acids and Bases”)