Acids are divided in following classes.
Strong Acids :
These are very corrosive and can cause severe skin burns.
e.g. Hydrochloric acid (HCI), sulphuric acid (H2SO4) and nitric acid (HNO3).
Sulphuric acid was the first acid discovered.
Weak Acids : These are mildly corrosive and normally do not affect the skin.
e.g. Citric acid, acetic acid, tartaric acid, etc.
Oxy Acids : The acids which have hydrogen and oxygen both are called oxy acid.
e.g. HNO3, H2SO4, and H3PO4, etc.
Hydra Acids : The acids which have hydrogen only but in it oxygen is absent are called hydra acids.
e.g. The acid like HCI, HBr, HCN, etc., are examples of hydra acid.
Organic Acid : Acids derived from plants and animals are called organic acids.
e.g. Citric acid in lemon and oxalic acid in tomato.
Inorganic Acid : Acids derived from minerals present in the earth's crust are called inorganic acids.
e.g. Sulphuric acid (H2SO4) and nitric acid (HNO3)
