This document provides information about acids, bases, and salts. It defines acids as sour substances that turn litmus blue and produce hydrogen ions in water. Acids are classified as organic, mineral, strong, or weak. Bases are defined as compounds that react with acids to form salts and water. Salts are formed by the combination of acids and bases and are found dissolved in seawater. Common examples of salts produced industrially include sodium chloride, sodium hydroxide, baking soda, and washing soda. The document also discusses the pH scale and provides examples of pH values for various substances.

1. ACIDS,BASES AND SALTS
Class 10

2. What are acids?
The word acid derives from the word acidus
meaning sour in taste.
Characterists of acids:
1. Sour in taste.
2. Turns blue litmus to blue.
3. Corrosive in nature.
4. When dissolved in water produces H+ ions.
5. Conduct electricity.

3. Some
naturally
occuring
acids

4. Classification of acids:
On the basis of origin:
● Organic acids- derives from livings organisms
like plants and animals
ex- acetic acid,citric acid
● Mineral acids- acids prepared from minerals
ex- HCL,HNO3

5. On the basis of origin
● Strong acids-acids which completeley dissociate
into ions
ex- H2SO4(sulphuric acid),HNO3(nirtic acid)
● Weak acids-acids which partially dissociate into
ions
ex- CH3COOH(acetic acid),H2CO3(carbonic
acid)

6. Chemical properties of acids:
1. METAL+ACID→ METAL SALT +HYDROGEN
ex- Fe+H2SO4→ FeSO4+H2(↑)
Cu+HNO3→Cu(NO3)2+H2(↑)
1. METAL CARBONATE/HYDROGEN
CARBONATE+ACID→ SALT+ CO2+H2O
ex- Na2Co3+HCL→NACL+CO2+H2O
CACO3+HCL→CACL2+CO2+H2O

7. 3. METAL OXIDE+ACID→SALT+WATER
ex- CuO+HCL→CUCL2+H2O
FeO+H2SO4→FeSO4+H2O
4. BASE+ACID→SALT+WATER
ex- NAOH+HCL→NACL+H2O
H+ + OH-→ H2O
What is dilution?
Dilution is the process of “lowering the concentration of
a solute in a solution by simply adding more solvent to
the solution, such as water

8. Indicators
any substance that gives a visible sign, usually by a
colour change in acidic or basic solution
● Natural indicators-those which can be extracted by plants.
For example: lichens, turmeric, china rose, and red
cabbage.
● Synthetic indicator-compounds that are manufactured in a
chemistry lab rather than obtained from nature.
For example- methyl orange, phenopthalein etc…
● Olfactory indicators-substances whose odour changes in
acidic or basic media
For example- Onion, vanilla, clove

10. What are bases?
A base is a compound which reacts with acid to form
salt and water only.
ex- CaO, NaOH, KOH etc….
Characterists of bases:
● Bitter in taste.
● Soapy to touch.
● Turn red litmus to blue.
● Conduct electricity.

11. Classification of bases:
1. On the basis of strength:
● Strong bases- bases which completeley
dissociate into ions in aqueous solution
ex- NaOH,KOH etc….
● Weak bases- bases which do not completely
dissociate into ions in aqueous solution.
ex- NH4OH, Ca(OH)2

12. Chemical properties of bases:
1. METAL+BASE→(HEAT)→SALT+HYDROGEN GAS.
Zn+NaOH→ →Na2ZnO2+H2(↑)
NaOH+Al+H2O→NaAlO2+H2(↑)
1. NON METALLIC OXIDE+BASE→METAL SALT+
WATER
CO2+NaOH→Na2CO3+H2O
CO2+Ca(OH)2→CaCO3+H2O

13. 3. BASE+ACID→SALT+WATER
NaOH+H2SO4→Na2SO4+H2O
NaOH+HNO3→NaNO3+H2O
When an acid is dissolved in water it always
produces H+ions.
When a base is dissolved in water it always
produces OH- ions.

14. HOW STRONG ARE ACID AND BASE SOLUTIONS?
The strength of acids and bases depends on the
number of H+ ions and OH– ions produced when
dissolved in WATER
Why water only?
Because water is an polar solvent with a high
dielectric constant. This property of water helps in
weakening the bond between ions and makes the
soluble.Hence acids and bases produce ions in
aqueous solutions only.

15. pH of some common substances
● 0- Battery acid.
● 1- Hydrochloric acid.
● 2- Lemon juice, gastric acid, Vinegar.
● 3- Grape fruit juice,Orange juice, Soda.
● 4- Tomato juice, Acid rain.
● 5- Black coffee.
● 6- Urine, Saliva.
● 7- Pure water.

16. ● 8- Sea water.
● 9- Baking soda.
● 10- Milk of magnesia.
● 11- Ammonia solution.
● 12- Soapy water.
● 13- Bleach, Oven cleaner.
● 14- Liquid drain cleaner.
*The pH of an neutral solution is 7.
*Value less than 7 represents an acidic solution.
*Value more than 7 represents a basic solution.

17. Salts

18. Salts
Salt is formed by the combination of
hydrochloric acid and sodium hydroxide
solution is called sodium chloride.
Sea water contains many salts dissolved in
it.Sodum chloride is saperated from these salts.
Common salt-A raw material for various
materials of daily uses such as sodium
hydroxide, baking soda, washing soda,
bleaching powder and many more!

19. Caustic soda (Sodium hydroxide, NaOH)
It is prepared by chlor-alkali process.In this
process electricity passed through a aqueous
solution of sodium chloride.Brine. decomposes to
sodium hydroxide.Chlorine gas formed at anode
and hydrogen gas at cathode.Sodium hydroxide
solution is formed near the cathode.
NaCl+H2O→NaOH+Cl(↑)+H2(↑)

20. Uses:
● Used as reagent in laboratories
● Soap manufacturing,purification of bauxite,
manufacturing of rayon.
● (NaOH) Production of chemicals such as
PVC,bleaching powder etc …….

21. Bleaching powder (calcium oxychloride,CaOCl2)
It is prepared by the action of chlorine on dry
slaked lime.
Ca(OH)2+Cl2→CaOCl2+H2O
Uses:
● As bleaching agent in textile,paper,jute
industry.
● As disinfectant for water to make it free of
germs
● As an oxidising agent in many industries.

22. Baking soda (sodium hydrogen carbonate (NaHCO3)
It is obtained by the reaction of brine with carbon di
oxide and ammonia.
NaCl+H2O+CO2+NH3→NH4Cl+NaHCO3
Uses:
● Used in cooking
● Used Antacid,it neutralises excess acid in stomach
● As fire extinguisher

23. Washing soda (sodium carbonate
decahydrate,NaCO3.10H2O)
It is prepared by the thermal decomposition of
sodium hydrogen carbonate by solvay process.
Cheif raw materials for the manufacture of
washing soda by solvay process are
1. Sodium chloride NaCl
2. Ammonia NH4
3. Limestone CaCO3

24. NaHCO3→(heat)→Na2CO3+H2O+Na+
Na2CO3+10H2O→crystallisation→Na2CO3.10H2O
Uses:
● Cleaning agent
● To remove permanent hardness of water
● Glass and paper industries
● manufacturing of important compounds like
borax etc…

25. Water of crystallisation
Water of crystallisation is the fixed number of
water molecules present in one formula unitof a
salt.

26. Plaster of Paris (calcium sulphate hemihydrate,
CaSO4.1/2H2O)
It is obtained by heating gypsum (CaSO4.2H2O) at
373k when it undergoes partial dehydration to give
plaster of Paris.
CaSO4.2H2O→CaSO4.1/2H2O+1 ½
Uses:
● In labo in laboratories for ceiling air caps in
apparatus to make it airtight.
● For ornamental caste and idols.
● For supporting fractured bones.