Online Notes on Chapter=2 ( Acids, Bases and Salts) Part 1

This is Online Notes on Chapter=2 ( Acids, Bases and Salts)  Part 1 for preparation of CBSE BOARD Examination, NTSE etc.






ACIDS :
• These are the substances which have sour taste.
• They turn blue litmus solution red.
• They give H⁺ ions in aqueous solution.
• The term ‘acid’ has been derived from the Latin word, acidus, which means
sour.

Strong Acids : HCl, H₂SO₄

, HNO₃

Weak Acids : CH₃COOH, Oxalic acid, Lactic acid

Concentrated Acid : Having more amount of acid + less amount of water

Dilute Acid : Having more amount of water + less amount of acid

BASES :
• These are the substances which are bitter in taste and soapy in touch.
• They turn red litmus solution blue.
• They give OH^-  ions in aqueous solution.

Strong Bases : NaOH, KOH, Ca(OH)₂

Weak Bases : NH₄OH

Alkalis : These are bases which are soluble in water [NaOH, KOH, Ca(OH)₂].

SALTS :

These are the compounds formed from reaction of acid and base.

Example : NaCl, KCl.

INDICATORS :
These are the substances which change their colour/smell in different types of
substances.

Reaction of Metallic Oxides with Acids

Metallic oxides are basic in nature.

E.g., CaO, MgO are basic oxides.

Metallic Oxide + Acid → Salt + H₂O

CaO + 2HCl → CaCl₂ + H₂O

Reaction of Non-metallic Oxides with Bases

Non-metallic oxides are acidic in nature.

Non-metallic Oxide + Base → Salt + H₂O

CO₂ + Ca(OH)₂ → CaCO₃ + H2O