Acids
Acids is defined as the one which produces hydrogen ions in water. For Example, Sulphuric Acid, Hydrochloric Acid etc. They give sour taste. Acids turn blue litmus to red. This is used as confirmation test for the presence of acid. When acids react with metals, gases are evolved.
Properties of Acids:
– Produce hydrogen ions [H+] in H2O.
– Sour taste.
– Turn blue litmus red.
– Act as electrolytes in Solution.
– Neutralize solutions carrying hydroxide ions.
– React with several metals releasing Hydrogen gas.
– React with carbonates releasing CO2 (g)
– Destroy body tissues.
– corrode metal surface quickly.
On the basis of origin, acids are classified as :
a. Organic acids: Acids derived from living organisms like plants and animals . For example: citric acid is present in fruits, acetic acid present in vinegar, oxalic acid present in tomato, tartaric acid present in tamarind, lactic acid present in sour milk and curd.
b. Mineral acids: They are also called inorganic acids. They are dangerous Example sulphuric acid (H2SO4), hydrochloric acid (HCl) etc.
On the basis of their strength, acids are classified as :
a. Strong acids: Completely dissociate into its ions in aqueous solutions.
Example: Nitric acid (HNO3), sulphuric acid (H2SO4), hydrochloric acid (HCl).
b. Weak acids: Weak acids are those acids which do not completely dissociate into
its ions in aqueous solutions. For example: carbonic acid (H2CO), acetic acid (CH3COOH).
On the basis of their concentration, acids are classified as :
a. Dilute acids: Have a low concentration of acids in aqueous solutions.
b. Concentrated acids: Have a high concentration of acids in aqueous solutions.
On the basis of number of hydrogen ion, acids can be classified as :
Monoprotic acid – Such type of acid produces one mole of H+ ions per mole of acid, e.g., HCl , HNO3
Diprotic acid – They can produce two moles of H+ ions per mole of acid, e.g., H2SO4.
Triprotic acid – They produce three moles of H+ ions per mole of acid, e.g., H3PO4.
Bases
Bases are the one which produces hydroxide ions in aqueous solutions. Bases which are water soluble they are known as Alkalis. They turn red litmus to blue. They have a bitter taste. They also produced carbon-dioxide when reacted with carbonates. They also evolved hydrogen gas when bases react with metals.
Properties of Base:
– Produce hydroxide ions [OH –] in H2O.
– Water soluble bases are called alkalies.
– Bitter Taste
– Turn Red Litmus blue.
– Act as electrolytes in Solution.
– Neutralize solutions containing H+ ions.
– Have a slippery, ‘soapy’ feel.
– Dissolve fatty material.
Salts
Salt is an ionic compound that results from the neutralization reaction of acids and bases. Salts are constituted of positively charged ions, known as cations and negatively charged ions, known as anions, which can either be organic or inorganic in nature. These ions are present in a relative amount, thus rendering the nature of the salt neutral
