Overview of Acids and Bases Class 10 Notes | EduRev

Science Class 10

Created by: Dr Manju Sen

Class 10 : Overview of Acids and Bases Class 10 Notes | EduRev

The document Overview of Acids and Bases Class 10 Notes | EduRev is a part of the Class 10 Course Science Class 10.
All you need of Class 10 at this link: Class 10

INTRODUCTION:-
A wide variety of materials consists essentially of elements and compounds having different characteristics exist around us. Some of them are sour, some are bitter, while some are salty in taste. For Ex:- Sour and bitter tastes of food are due to acids and bases, respectively, present in them.
Acids react with bases to produce salt whose properties are different from acid and base.


ACIDS

The term "acid" is derived from the latin word "acidus" meaning sour to taste.

  • 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.

Example:- Sour taste of lemon, unripened grapes, Vinegar, tomatoes etc.Overview of Acids and Bases Class 10 Notes | EduRevFig: Svante Arrhenius

According to Arrhenius theory:- "An acid is a substance which dissolved in water, it ionizes and releases hydrogen ions [H+(aq.)] in solution".

              Overview of Acids and Bases Class 10 Notes | EduRev

       

         Overview of Acids and Bases Class 10 Notes | EduRev


Note- Hydrogen ion do not exist as H+ ions in solution, they attach themselves to the polar water molecules to form hydronium ions or hydroxonium ions, (H3O+ or H+(aq)

                    Overview of Acids and Bases Class 10 Notes | EduRev


Reaction of Acids

1. Reaction of Acid with Metal

                                     Acid + Metal → Salt + Hydrogen gas

                                     Mg + HSO4 → H2 + Mg SO4

2. Reaction of Acid with Carbonates

                                    Na2 CO(s) + 2 HCl (aq) → 2NaCl (aq) + H2O(l) + CO2(g)

3. Reaction of Acid with Bicarbonates

                                   NaHCO3 (s) + HCl (aq) → NaCl(aq) + H2O (l) + CO(g)


Classification of Acids

(I) Acids are classified as Organic and Mineral acids. Acids which are derived from plants and animals, they are known as Organic Acids. For ex, Citric Acid from fruit. Mineral acids are inorganic acids such as Sulphuric Acid. They are dangerous to be used, so need more precautions. 


(i) Mineral Acids (Inorganic acids)-
The acids which are usually obtained from minerals are known as inorganic acids.


NameChemical FormulaWhere found or used
Hydrochloric acidHClIn purification of common salt, in textile industry as a bleaching agent, to make aqua regia.
Nitric AcidH2SO4Commonly used in car batteries, in the manufacture of fertilizers (Ammonium phosphate, Super phosphate detergents etc, in paints, plastics, drugs)
Carbonic AcidHNO3manufacture of artificial silk, in petroleum refining.


Used in the manufacture of explosives (TNT, Nitroglycerine) and fertilizers (Ammonium nitrate, Calcium nitrate, Purification of Au, Ag.
Phosphoric acidH3PO4Used in anti-rust paints and in fertilizers


Note- Aqua regia is a mixture of (3 part HCl & 1 part HNO) which dissolves even noble metals like Au, Pt.


(ii) Organic Acids-

Overview of Acids and Bases Class 10 Notes | EduRevFig: Citric acid example of organic acids

The acids which are usually obtained from plants and animals are known as organic acids.

NameWhere found or used
Formic acid (HCOOH)Found in the stings of ants and bees, used in tanning leather, in medicines for treating gout.
Acetic acid (CH3COOH)Found in vinegar, used as solvent in the manufacture of dyes and perfumes.
Lactic acidResponsible for sourcing of milk in curd
Benzoic acidUsed as a food preservative
Citric acidPresent in lemon, orange and citrus fruits
Tartaric acidPresent in tamarind.


(II) On the Basis of their Basicity:-

"The basicity of an acid is the number of replaceable hydrogen atoms present in a molecule that can be produced by the complete ionisation of one molecule of that acid in aqueous solution."
or "Basicity of an acid is determined by number of hydronium ions (H3O+/H+(aq) produced per molecule of acid on ionisation."


(i) Monobasic Acids-
The acid on complete ionisation produce one hydronium ion in aqueous solution.
Example- Hydrochloric acid (HCl)
Hydrobromic acid (HBr)
Hydrofluoric acid (HF)
Hydroiodic acid (HI)
Nitric acid (HNO3)
Acetic acid (CH3COOH)
Formic acid (HCOOH)

Overview of Acids and Bases Class 10 Notes | EduRev

Overview of Acids and Bases Class 10 Notes | EduRev

Overview of Acids and Bases Class 10 Notes | EduRev


(ii) Dibasic Acid-
The acid on complete ionisation produces two hydronium ions in aqueous solution.
Example- Sulphuric acid (H2SO4)
Carbonic acid (H2CO3)
Oxalic acid (COOH)2

Overview of Acids and Bases Class 10 Notes | EduRev

Overview of Acids and Bases Class 10 Notes | EduRev


(iii) Tribasic Acid-
The acid on complete ionisation produces three hydronium ions in aqueous solution.
Example-
Overview of Acids and Bases Class 10 Notes | EduRev

(III) Classification on the basis of their strength:-

(i) Strong Acid-
The acid which undergoes complete ionisation in aqueous solution is known as strong acids.
Example-

Overview of Acids and Bases Class 10 Notes | EduRev


(ii) Weak Acid-
The acid which undergoes partial or incomplete ionisation in aqueous solution is known as weak acids.
Overview of Acids and Bases Class 10 Notes | EduRev

Example- Formic acid (HCOOH)
Oxalic acid (COOH)2
Carbonic acid (H2CO3)
Phosphoric acid (H3PO4)

(IV) Classification on the basis of concentration of the Acid:- 

(i) Concentrated Acid-
The acids which contains very small amount of water is called a concentrated acid.


(ii) Dilute Acid-                 

Overview of Acids and Bases Class 10 Notes | EduRevFig: Dilution of acidThe acids which contain more amount of water is called a dilute acid.
"Strength of an acid does not depend upon the concentration of an acid"
Strength of an Acid ∝ Concentration of hydronium ion.


BASES
Substances with bitter taste and give a soapy touch are known as bases but many bases have corrosive nature. 

Properties of Bases:
– 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.


According to Arrhenius:-

"Those substances which give hydroxide or hydroxyl ion (OH-) in their aqueous solution" are called bases.

NaOH(aq.) → Na+(aq) + OH-(aq)
KOH(aq.) → K+(aq) + OH-(aq)
Example- Sodium hydroxide (NaOH)
Zinc oxide (ZnO)
Copper oxide (CuO)
Calcium hydroxide [Ca(OH)2]
Aluminum hydroxide [Al(OH)3]


The compounds which are either metallic oxides or metallic hydroxides. Which combines with acids to form salts and water only.

Overview of Acids and Bases Class 10 Notes | EduRev

Alkalis:-
Bases which completely dissolves in water are called alkalis.
Examples-  KOH, NaOH, Ca(OH)2
All the alkalis are bases but all bases are not alkalis.
Examples- [Fe(OH)3] ferric hydroxide and cupric hydroxide [Cu(OH)2] are base, but not an alkali.


Reactions of Bases

1. Reaction with Metals

Base reacts with metals and produce hydrogen gas.

                                         2NaOH + Zn → Na2 → Na2ZnO2 + H2

2. Reaction with Acids

Base reacts with acids to form salts. For Example,

                                         KOH + HCl → KCl + H2O

3. Reaction with Non-metallic Oxides

Base reacts with non-metallic oxides to form salt and water.

                                          2NaOH + CO2 → CO → Na2CO3 + H2O


Classification of Bases-
(I) Classification on the basis of their strength:-

(i) Strong alkalis or bases-
The alkalis or bases which undergo almost complete ionisation in aqueous solution are known as strong alkalis or bases.
Examples-

Overview of Acids and Bases Class 10 Notes | EduRev


(ii) Weak alkalis or bases-
The alkalis or bases which undergo only partial ionisation in aqueous solution are known as weak alkalis or Bases.
Example-

Overview of Acids and Bases Class 10 Notes | EduRev


(II) Classification on the basis of their concentration:-

(i) Concentrated Base or Alkali-
The bases or alkalis which contain a very small amount of water is called concentrated bases or alkalis.
(ii) Dilute Base-
The bases or alkali which contain more amount of water is called a dilute bases or alkalis


(III) Classification on the basis of their acidity:- 

Overview of Acids and Bases Class 10 Notes | EduRevFig: Soaps are basic in natureAcidity of a base is determined by the number of hydroxyl (OH-) ions produced by per molecule of a Base or Alkali on complete dissociation in water "or"
The "number of hydrogen ions of an acid with which a molecule of that alkali or base react to produce salt and water is known as acidity of an alkali or Base".

(i) Mono acidic Bases or Alkali-
The base or alkali on complete ionisation produces one hydroxyl (OH_) ion in aqueous solution.
Example-

Overview of Acids and Bases Class 10 Notes | EduRev


(ii) Diacidic Bases (or alkalis)-
The base or alkali on complete ionization produce two hydroxyl ion (OH-) in aqueous solution
Example-
(A) Diacidic Bases of-
Ca(OH)2(aq.) → Ca2+(aq.) + 2OH-(aq.)
Mg(OH)2(aq.) → Mg2+(aq.) + 2OH-(aq.)

(B) Diacidic Bases -
Ferrous hydroxide [Fe(OH)2] and copper hydroxide [Cu(OH)2]
Fe(OH)2(aq.) → Fe2+ + 2OH-(aq.)
Fe+2(OH)2- + 2H+Cl-(aq.) → FeCl2 + 2H2O


(iii) Tri Acidic Bases-
The base or alkali on complete ionization produces three hydroxyl ion (OH)- in aqueous solution.
Example- Aluminium hydroxide [Al(OH)3], Ferric hydroxide [Fe(OH)3]
Al(OH)3(aq.) → Al3+(aq.) + 3OH-(aq.)
Al3+(OH)3- + 3HCl(aq.) → AlCl3 + 3H2O

Share with a friend

Complete Syllabus of Class 10

Dynamic Test

Content Category

Related Searches

study material

,

Summary

,

video lectures

,

ppt

,

Overview of Acids and Bases Class 10 Notes | EduRev

,

Overview of Acids and Bases Class 10 Notes | EduRev

,

Sample Paper

,

Viva Questions

,

Overview of Acids and Bases Class 10 Notes | EduRev

,

practice quizzes

,

past year papers

,

Free

,

Extra Questions

,

Exam

,

MCQs

,

pdf

,

shortcuts and tricks

,

Semester Notes

,

Important questions

,

Previous Year Questions with Solutions

,

Objective type Questions

,

mock tests for examination

;