Study Notes Acid Bases and Salts Class 10 Science Chapter 2

Class 10 Science Notes Chapter 2 : Acids Bases and Salts are available here for students and teachers for education purpose.

Class 10 Science Chapter 2 Acid Bases and Salts

Class 10 Science Chapter 2is Acid Bases and Salts . This second chapter of science class 10 is very useful for exam point of view. This chapter consists of the topics – Acids, Bases, Salts, Reaction of Acid with Metal, Metal Carbonates and Metal Hydrogen Carbonates; Reaction of Base with Metals , Acids, Neutralisation, Chemical Properties of Bases and Acids; Indicators, Universal Indicators, Olfactory Indicators, Natural and Synthetic Indicators; Antacids, Litmus Solution, pH Scale, Common Salt, Bleaching Powder, Baking Soda, Washing Soda, Plaster of Paris ( P.O.P.) , Sodium Hydroxide, etc.

Chapter 2 : Acid Bases and Salts

ChapterChapter 2 : Acid Bases and Salts
SubjectScience
Study MaterialStudy Notes ( Short Notes)
Class10 ( Class – X )
Text bookNCERT Textbook of Science for Class X

Class 10 Science Notes Chapter 2 ( Study Notes )

1. Acids : Any substance which turns blue litmus to red and sour in taste are known as Acids .
Example : Vinegar, Sulphuric Acid, NaOH.

2. Properties of Acids :
a) Acids are Sour in taste.
b) Acids change the colour of blue litmus to red.
c) Acids dissolve in water to form H+ ion.
d) Acids have pH value less than 7 .

3. Reaction of Acids with Metals
a) Acid  +  Metal  → Salt  +  Hydrogen gas
b) Acids react with metal to form salt and Hydrogen gas.
c) 2HCl  + 2Zn  → ZnCl2  + H2

4. Reaction of Acid with metal Carbonates and Metal Hydrogencarbonates
a) All Metal Carbonate / Metal Hydrogencarbonates   +  Acid  → Salt  + CO2 + Water
b) Acid reacts with Metal Carbonates and Metal Hydrogencarbonates to form  Salt , water, and Carbon Dioxide gas
c) Na2CO3  +  2HCl  →  2NaCl  +  H2O  +  CO2
d) NaHCO3  +  HCl  → NaCl  +  H2O +  CO2

5. Reaction of Acid with Base : Acids and Base react with each other to form salt and water . This process is called Neutralization
a) Base  +  Acid  →  Salt  +  Water
b) NaOH   +   HCl  →  NaCl  + H2O

6. Reaction of Acids with Metallic Oxides
a) Metal oxide  + Acid  →  Salt  +  Water

7. Base : Any substance which turn red litmus to blue and is bitter in taste is known as a Base.

8.) Chemical Properties of Bases
a) Bases are bitter in taste.
b) Bases change the colour of Red Litmus to Blue .
c) Base has pH value more than 7.
d) Bases generate OH- ions in water.

8. Reaction of Base with Acids : Acids and Base react with each other to form salt and water . This process is called Neutralization.
a) Base  +  Acid  →  Salt  +  Water
b) NaOH   +   HCl → NaCl  + H2O

9. Indicators : Materials which indicate the presence of Acid or Base in a Solution/ Compound are known as Indicators or acid-base Indicators

10. Universal Indicators :  It is a mixture of many Indicators  which gives different colours at different value of pH.

11. Olfactory Indicators:  Those Indicators which tell the presence of acid or base by changing their Odour( when come in contact of acid or base) are known olfactory indicators.
Example Onion, Clove Oil, Vanilla Extract.

12. Natural Indicators  : Natural Indicators are found naturally .
Example : Litmus

13. Synthetic Indicators : Synthetic Indicators are synthesized in laboratory .
Example : Methyl Orange, Phenolphthalein

14. Litmus Solution :  It is a purple dye which is extracted from lichen

15. Alkali : Bases which are soluble in water are known as Alkali.

16. Antacids : Antacids neutralise the effect of acid.
Example : Magnesium Hydroxide (Milk of Magnesia)

17. pH Scale. : pH stands for ‘potenz’ in German. The pH scale is a scale that is used for measuring the concentration of hydrogen ion in a solution. “Potenz” means Power.
a) Acidic : pH value 0 to 6
b) Neutral : pH value 7
c) Base : pH value 8 to 14
d) Acid Rain : pH value of rainwater is less than 5.6
e) pH in tooth decay : Tooth decay starts when pH in mouth is less than 5.5

18. Common Salt
a) Chemical Name : Sodium Chloride
b) Chemical Formula : NaCl
c) Formation : Obtained from Sea.
d) Uses : Used in food ; used in formation of other salts like Baking Soda, etc.

19. Bleaching Powder :  It is a salt
a) Chemical Name : Calcium Oxy Chloride
b) Chemical Formula : CaOCl2
c) Formation : Ca(OH)2  +  Cl2 → CaOCl2  + H2O
d) Uses :  to kill germs from water ; Used as oxidising agent ; for bleaching cotton, wood pulp, linen, etc

20. Baking Soda: It is a mild non-corrosive salt
a) Chemical Name : Sodium Hydrogen Carbonate
b) Chemical Formula : NaHCO3
c) Formation : NaCl  + H2O + CO2  +  NH3  -> NH4Cl  + NaHCO3
d) Uses :  Used in Kitchen for making food items like bhatura , pakora, etc ; used in Antacids ; Used for making Baking Powder ; Used in Soda-acid fire extinguishers.
e) Formation of Baking Powder from Baking Soda :
NaHCO3  + H →  CO2 + H2O + Sodium salt of Acid

21. Washing Soda : It is a salt.
a) Chemical Formula : – Na2CO3.10H2O
b) Formation :  Na2CO3  +  10H2O -> Na2CO3.10H2O
c) Uses : Used in Soaps, glass, and paper industries ; to remove permanent hardness of water ; cleansing agent ; to  manufacture borax.

22. Plaster of Paris
a) Chemical Name : Calcium Sulphate hemihydrate
b) Chemical Formula : CaSO4.½H2O
c) Uses : Used by doctors for supporting the fracture bone of the patient. ; for making toys ; making smooth surface etc
d) Properties : CaSO4.½H2O  + 1½H2O → CaSO4.2H2O

23. Sodium Hydroxide
a) Chemical Formula : NaOH
b) Chlor -alkali Process : When Aqueous solution of Sodium Chloride is passed through it decomposes to form Sodium Hydroxide. This process is called Chlor-alkali process.
2NaCl(aq)  +  2H2O -> 2NaOH  +  Cl2  + H2

24. Example of Natural Acids

SourceAcid Name
VinegarAcetic Acid
OrangeCitric Acid
CurdLactic Acid
LemonCitric Acid
TamarindTartaric Acid
TomatoOxalic Acid
Ant Sting and Nettle StingMethanoic Acid

Chemical Reaction used in the chapter

1) 2NaOH  +  Zn  → Na2ZnO2  +  H2
2) 2NaOH  +  Zn  → Na2ZnO2  +  H2
3) Na2CO3  +   2HCl  → 2NaCl   +   H2O  + CO2
4) NaHCO3  +  HCl  → NaCl  + H2O  + CO2
5) Ca(OH)2  +  CO2  → CaCO3  +  H2O

6) CaCO3  +  H2O  + CO2  → Ca(HCO3)2
7) NaOH  + HCl  → NaCl  +  H2O
8) 2Nacl  +  2H2O →  2NaOH  +  Cl2  +  H2
9) Ca(OH)2  +  Cl2 →  CaOCl2  +  H2O
10) NaCl  +  H2O  +  CO2  +  NH3 → NH4Cl  +  NaHCO3

11) 2NaHCO3 →  Na2CO3  + H2O  +  CO2
12) NaHCO3  +  H+  → CO2 + H2O  +  Sodium Salt of Acid
13) Na2CO3  + 10H2O → Na2CO3.10H2O
14) CaSO4.½H2O  + 1½H2O  →  CaSO4.2H2O

Chemical Names of Compound used in the Chapter

1. Sodium Zincate : Na2ZnO2
2. Lime Water : Ca(OH)2
3. Bleaching Powder : CaOCl2
4. Ammonium Chloride : NH4Cl
5. Sodium Hydrogencarbonate : NaHCO3
6. Sodium Carbonate : Na2CO3
7. Plaster of Paris (Calcium Sulphate hemihydrate) : CaSO4.½H2
8. Gypsum : CaSO4.2H2O