© Blueprint Education (A Division of Chitra Prakashan (I) Pvt. Ltd.)

Colourlessfor Acids

PhenolphthaleinColourless for neutral

Pink for Bases

Methyl orange

Litmus Sol’’

Yellowfor Bases

Orangefor Nutrual

Red for Acids

Blue for Bases

Indicators

chemical substances which give colours in acidic and basic solution.

classified bypH Scale

+Concentration of H ions in a solution

< 7 for a base

< 7 for an acid

< 7 for neutral solution

ACIDS & BASES

Acids

Substances that are sour +in taste and give H ions

in aq. solution.

Types

Compounds formed when hydrogen of an acid is replaced by a metal in displacement reaction

Substances which are bitter in –taste and give OH ions in aq.

solution

Salts

Bases

Mineral AcidsExample

Example

Example

Acids obtained from minerals like sulphates, nitrates, chlorides etc.

H So , 2 4

HNO , 3

HCl

Citric Acid, Ascorbic acid lactic Acid

Conc. Hcl, Con.HNO , 3

Conc. H SO2 4

Organic Acids

Acids obtained from plants and animals

Concentrated Acids

Acids containing minimum amount of water

Properties

Reaction with Metals

Reaction with Metal Carbonates

Neutralisatin Reactin

Metal + Acid Salt + Hydrogen Eg.2HCl + Zn ® ZnCl + H2 2

Metal + Acid ® Salt + Co + H O carbonate 2 2

Eg.Na CO + 2HCl ® 2NaCl + H O2 3 2 2

Acid + Base ® Salt + Water

EgHCl + NaOH ® NaCl + H O2

Reaction with Metal Oxides

Metal oxide + Acid ® Salt + water CuO +

2HCl ® CuCl + H O2 2

Important Salts

Common Salt (NaCl)

Caustic Soda (NaCl)

Uses

Uses

Obtained by the reaction of NaOH and Hcl NaOH + Hcl ® NaCL + H O2

Obtained when electricity is passed through an aq. sol of NaCl. 2NaCl + 2H O®2NaOH+ Cl + H O2 2 2

(aq) (l) (aq) (g) (g)

In food and synthesis of NaOH, H2, Cl etc.2

For making soaps, detergents, artificial textiles etc.

Bleaching powder (CaOCl )2

Baking Soda (NaHCO )3

Uses

Uses

Obtained when Cl gas is passed 2

through dry slaked lime [Ca(OH) ]2

Ca(OH) + Cl ®2CaOCl + H O2 2 2 2

Prepared by passing Co2 gas through a cold saturated sol of Sod. CarbonateNaCl + H O+ Co + NH ®NH4Cl + 2 2 3

NaHCO2

As disinfectant germinate deodorant, in making chloroform

As ingredient in anti-acid medicine in cooking wod.

Washing soda (Na CO . 10H O)2 3 2

Plaster of Paris (CaSO .1/2H O)4 2

Uses

Uses

Obtained by recrystallisation of Sod.Carbonate Na CO + 10H O®2 3 2

Na CO O10H O2 3 2

Prepared by heating gypsum at CaSO .2H O® CaSO .1/2 4 2 4

H2O + H2O

For softening hard water, as laboratory reagent in glass, soap and paper industry

In orthopedics, for making casts of statues, toys and as a fireproofing material

®373 k

®373 k

Caustic Soda (NaCl) Uses

Obtained when electricity is passed through an aq. sol of NaCl. 2NaCl + 2H O®2NaOH+ Cl + H O2 2 2

(aq) (l) (aq) (g) (g)

For making soaps, detergents, artificial textiles etc.

Bleaching powder (CaOCl )2

Baking Soda (NaHCO )3

Uses

Uses

Obtained when Cl gas is passed 2

through dry slaked lime [Ca(OH) ]2

Ca(OH) + Cl ®2CaOCl + H O2 2 2 2

As disinfectant germinate deodorant, in making chloroform

As ingredient in anti-acid medicine in cooking wod.

Washing soda (Na CO . 10H O)2 3 2

Plaster of Paris (CaSO .1/2H O)4 2

Uses

Uses

Obtained by recrystallisation of Sod.Carbonate Na CO + 10H O®2 3 2

Na CO O10H O2 3 2

Prepared by heating gypsum at CaSO .2H O® CaSO .1/2 4 2 4

H2O + H2O

For softening hard water, as laboratory reagent in glass, soap and paper industry

In orthopedics, for making casts of statues, toys and as a fireproofing material®373 k

Types

Bases which completely dissociate in water into

–cation and OH ion.

Strong Base

Acids, Bases and SaltsChapter-2

Acids and Bases

AcidsSubstances that are sour

+in taste and give H ions in aqueous solution.

Types

Mineral AcidsAcids obtained from minerals like sulphates, nitrates, chlorides etc.

ExampleH So , HNO , HCl2 4 3

Example

Conc. HCl, Conc. HNO , Conc. H SO3 2 4

Organic AcidsAcids obtained from plants and animals.

Concentrated AcidsAcids containing a minimum amount of water.

Properties

Reaction with Metals

Metal + Acid ® Salt + Hydrogen

e.g. 2HCl + Zn ® ZnCl + H2 2

Reaction with Metal Carbonates

Metal carbonate + Acid ® Salt + Co + H O 2 2

e.g. Na CO + 2HCl ® 2NaCl + CO + H O2 3 2 2

Neutralisation ReactionAcid + Base ® Salt + Water

e.g. HCl + NaOH ® NaCl + H O2

Reaction with Metal Oxides

Metal oxide + Acid ® Salt + water

CuO + 2HCl ® CuCl + H O2 2

Important Salts

Common Salt (NaCl)Obtained by the reaction of NaOH and HCl.NaOH + HCl ® NaCl + H O2

UsesIn food and synthesis of NaOH, H , Cl etc.2 2

UsesFor making soaps, detergents, artificial textiles etc.

Bleaching Powder (CaOCl )2

Obtained when Cl gas is passed 2

through dry slaked lime [Ca(OH) ].2

Ca(OH) + Cl ®2CaOCl + H O 2 2 2 2

Baking Soda (NaHCO )3

Prepared by passing Co gas through 2

a cold saturated solution of sodium carbonate.NaCl + H O+ Co + NH ®NH Cl + 2 2 3 4

NaHCO3

UsesAs disinfectant germinate deodorant, in making chloroform

Uses As an ingredient in anti-acid medicine in cooking food.

Washing Soda (Na CO .10H O)2 3 2

Obtained by recrystallisation of Sodium carbonate. Na CO + 10H O®Na CO .10H O 2 3 2 2 3 2

UsesFor softening hard water as laboratory reagent, in glass, soap and paper industry.

UsesIn orthopedics, for making casts of statues, toys and as a fireproofing material.

ExampleNaOH, KOH

Weak BaseBases which partially dissociates in water.

Types

C NCEPT MAP

Combination

Example

NH OH4

Properties

Reaction with MetalsBases combine with only reactive metals like sodium and potassium. e.g. 2NaOH + Zn ® Na ZnO + H2 2 2

Reaction with Non-metallic OxidesNon-metallic oxides react with bases to form salt and water. e.g. Ca(OH) + CO ® CaCO + H O2 2 3 2

AlkaliBases soluble in water. e.g.

+ –NaOH ® Na + OH

SaltsCompounds formed when hydrogen of an acid is replaced by a metal in displacement reaction.

Bases

Substances which are bitter in –

taste and give OH ions in aqueous solution.

Plaster of Paris (CaSO .1/2H O)4 2

Prepared by heating gypsum at 373 k.

CaSO .2H O ¾® CaSO .1/2 H O 4 2 4 2

+ H O2

D

Strong BaseBases which completely dissociate in water into

–cation and OH ion.

Caustic Soda (NaOH)Obtained when electricity is passed through an aqueous sol of NaCl. 2NaCl + 2H O®2NaOH+ Cl + H2 2 2

(aq) (l) (aq) (g) (g)

ExampleCitric acid, Ascorbic acid, lactic acid

Colourless for Acids

Colourless for Neutral

Pink for Bases

IndicatorsChemical substances which give different colours in acidic and basic solution.

pH Scale+Concentration of H ions

in a solution.> 7 for a Base

< 7 for an Acid

= 7 for Neutral Solution

Phenolphthalein

Methyl Orange

Litmus Solution

Orange for Neutral

Red for Acids

Blue for Bases

Cla

ssif

ied

by

Red for Acids

Yellow for Bases