TNPSC Free Notes Chemistry – Chemical properties of Acids, Base and Salt

இந்தக் கட்டுரையில், TNPSC குரூப் 1, குரூப் 2, குரூப் 2A, குரூப் 4 மாநிலப் போட்டித் தேர்வுகளான TNUSRB, TRB, TET, TNEB போன்றவற்றுக்கான  முறைகள் இலவசக் குறிப்புகளைப் பெறுவீர்கள்.தேர்வுக்கு தயாராவோர் இங்குள்ள பாடக்குறிப்புகளை படித்து பயன்பெற வாழ்த்துகிறோம்.

Chemical properties of Acids, Base and Salt

Chemical Properties of Acids
Metals with Acids
 Metal + Acid → Salt + Hydrogen
 Ag, Cu Do not liberate Hydrogen
 Mg + H 2 SO 4 MgSO 4 + H 2
Metal Carbonate (or) Metal bicarbonate with Acids
 Metal carbonate (or) Metal bicarbonate + Acid → Salt + Water + Carbon dioxide
 MgCO 3 + 2HCl → MgCl 2 + H 2 O + CO 2
 Mg(HCO 3 ) + 2HCl → MgCl 2 + 2H 2 O + 2CO 2
Metallic oxides with Acids
 Metallic Oxide + Acid → Salt + Water
 CaO + 2HCl → CaCl 2 + H 2 O

Water with Acids
 Acid + Water →Hydrogen ion+
 HCl + H 2 O → H 3 O + + Cl –

Chemical Properties of Base
Metals with base
 Metal + Base → Salt + Hydrogen
 Zn + 2NaOH → Na2 ZnO2 + H2↑ [Sodium Zincate]
Non – Metallic oxides with Base
 Non-Metallic Oxides + Bases → Salt + Water
 2NaOH + CO2 → Na2CO3 + H2O [Sodium Carbonate]
Water with Base
 Base + Water → Hydroxide ions
 NaOH – Do not react with Cu, Ag, Cr
 NaOH → Na+ + OH-

Acid + Base → Salt + Water
HCl + NaOH → NaCl + H 2 O
Uses of Acids
 H 2 SO 4 – Car Batteries
 HNO 3 – Fertilizer
 HCl – Cleansing toilets
 C 4 H 6 O 6 – Tartaric acid – Baking Powder
 H 2 CO 3 – carbonic acid – Aerated drinks
 C 7 H 6 O 2 – Benzoic Acid – Food Preservative
Uses of Base
 NaOH – Soap manufacturing
 Ca(OH) 2 – White Washing
 Mg(OH) 2 – Medicine For Stomach Disorder
 NH 4 OH – Removal of Grease from cloths
Salt

Characteristics of Salts
 Acid + Base → Salt + Water + Heat [Neutralization]
 Mostly Solids
 Soluble in Water (Exception: Silver Chloride)
 Odourless
 Hygroscopic Nature
Identification of Salts
 Physical Examination
 Dry Heating Test
 Flame Test
Flame Test
Salt + HCl Paste is heated with help of Platinum Wire

Classification of Salts
Normal Salt

 A normal salt is obtained bycomplete neutralization of an acid by a base.
 NaOH + HCl → NaCl + H 2 O
Acid Salt
 It is derived from the partialreplacement of hydrogen ions of an acidby a metal. When a
calculated amount of a base is added to a polybasic acid, acid salt is obtained.
 NaOH + H 2 SO 4 → NaHSO 4 +H 2 O

Basic Salt
 Basic salts are formed by the partial replacement of hydroxide ions of adiacidic or
triacidic base with an acid radical.
 Pb(OH 2 ) + HCl → Pb(OH)Cl +H 2 O
Double Salt
 Double salts are formed by the combination of the saturated solution of twosimple salts
in equimolar ratio followed by crystallization.
 Simple Salt + Simple Salt → Double Salt
 E.g. Potash AlumKAl(SO 4 ) 2 .12H 2 O
Uses of Salts
 Common Salt (NaCl)
o Food Préservative
 Washing Soda (Na 2 CO 3 )
o Softening Hard Water
o Cleaning Agent for Domestic Purposes
 Baking Soda (NaHCO 3 )
o Making of Baking Powder
o Neutralizes Acidity in Stomach
 Bleaching Powder (CaOCl 2 )
o Disinfecting drinking water free from micro organism
o To bleach cotton & linen
 Plaster of Paris (CaSO 4 . ½ H 2 O)
o Plastering fractured bones

o Making casts for statues
 Gypsum Salt (CaSO 4 . 2H 2 O)
o Making Fertilizer
o Making Cements
 Epsom Salt (MgSO 4 . 7H 2 O)
o Medicine for Stomach Disorder

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