12th standard chemistry public exam important questions 2022 in volume 2

12th standard chemistry public exam important questions 2022 in volume 2

12th standard public exam 2022 chemistry important questions

Unit 8 IONIC 

EQUILIBRIUM

1. What are Lewis acids and bases? Give two example for each.

2. Discuss the Lowry – Bronsted concept of acids and bases.

6. The concentration of hydroxide ion in a water sample is found to be 2.5 10 M-6 × . Identify

the nature of the solution.

8. Calculate the pH of 0.04 M HNO3

 Solution.

9. Define solubility product

10. Define ionic product of water. Give its value at room temperature.

11. Explain common ion effect with an example

12. Derive an expression for Ostwald’s dilution law

13. Define pH

18. Derive an expression for the hydrolysis constant and degree of hydrolysis of salt of strong

acid and weak base.

Unit 9 ELECTRO 

CHEMISTRY

1.Define anode and cathode

2.Why does conductivity of a solution decrease on dilution of the solution

3.State Kohlrausch Law. How is it useful to determine the molar conductivity of weak

electrolyte at infinite dilution.

4.Describe the electrolysis of molten NaCl using inert electrodes

5.State Faraday’s Laws of electrolysis

6.Why is anode in galvanic cell considered to be negative and cathode positive electrode?

7.Why is anode in galvanic cell considered to be negative and cathode positive electrode?

8.Why is AC current used instead of DC in measuring the electrolytic conductance?

9.The same amount of electricity was passed through two separate electrolytic cells containing

solutions of nickel nitrate and chromium nitrate respectively. If 2.935g of Ni was deposited

in the first cell. The amount of Cr deposited in the another cell? Give : molar mass of Nickel

and chromium are 58.74 and 52gm-1 respectively.

10.Derive an expression for Nernst equation

11.Write a note on sacrificial protection.

Unit 10 SURFACE 

CHEMISTRY

1.Give two important characteristics of physiscorption

2.Differentiate physisorption and chemisorption

3.In case of chemisorption, why adsorption first increases and then decreases with

temperature?

4.Peptising agent is added to convert precipitate into colloidal solution. Explain with an

example.

5.Addition of Alum purifies water. Why?

6.Describe some feature of catalysis by Zeolites.

7.Give three uses of emulsions.

8.Write a note on electro osmosis

9.Describe adsorption theory of catalysis.

Unit 11 HYDROXY COMPOUNDS

AND ETHERS

1.Draw the major product formed when 1-ethoxyprop-1-ene is heated with one equivalent

of HI.

2.Suggest a suitable reagent to prepare secondary alcohol with identical group using Grignard

reagent.

3.What is the major product obtained when two moles of ethyl magnesium bromide is

treated with methyl benzoate followed by acid hydrolysis.

4.What happens when 1-phenyl ethanol is treated with acidified KMnO4

.

5.Write the mechanism of acid catalysed dehydration of ethanol to give ethene.

6.Explain Kolbe’s reaction

7.What is metamerism? Give the structure and IUPAC name of metamers of 2-methyoxy

propane

Unit 12 CARBONYL 

COMPOUNDS AND 

CARBOXYLIC ACIDS

1.How will you prepare

i. Acetic anhydride from acetic acid

ii. Ethylacetate from methylacetate

iii. Acetamide from methylcyanide

iv. Lactic acid from ethanal

v. Acetophenone from acetylchloride

vi. Ethane from sodium acetate

vii. Benzoic acid from toluene

viii. Malachitegreen from benzaldehyde

ix. Cinnamic acid from benzaldehyde

x. Acetaldehyde from ethyne

Unit 13 ORGANIC NITROGEN

COMPOUNDS

1.Write down the possible isomers of the C H4 9NO2 give their IUPAC names

2. There are two isomers with the formula CH NO23 . How will you distinguish between them?

3.Write short notes on the following

i. Hofmann’s bromide reaction

ii. Ammonolysis

iii. Gabriel phthalimide synthesis

iv. Schotten – Baumann reaction

v. Carbylamine reaction

vi. Mustard oil reaction

vii. Coupling reaction

viii. Diazotisation

ix. Gomberg reaction

4.Account for the following

i. Aniline does not undergo Friedel – Crafts reaction

ii. Diazonium salts of aromatic amines are more stable than those of aliphatic amines

iii. pKb of aniline is more than that of methylamine

iv. Gabriel phthalimide synthesis is preferred for synthesising primary amines.

v. Ethylamine is soluble in water whereas aniline is not

vi. Amines are more basic than amides

vii.Although amino group is o – and p – directing in aromatic electrophilic substitution

reactions, aniline on nitration gives a substantial amount of m – nitroaniline.

5.A dibromo derivative (A) on treatment with KCN followed by acid hydrolysis and heating

gives a monobasic acid (B) along with liberation of CO2 . (B) on heating with liquid

ammonia followed by treating with Br2 /KOH gives (c) which on treating with NaNO2

and HCl at low temperature followed by oxidation gives a monobasic acid (D) having

molecular mass 74. Identify A to D.

Unit 14 BIOMOLECULES

1. What type of linkages hold together monomers of DNA?

2. Give the differences between primary and secondary structure of proteins.

3. Name the Vitamins whose deficiency cause i) rickets ii) scurvy

4. Write the Zwitter ion structure of alanine

5. Give any three difference between DNA and RNA

6. Write a short note on peptide bond

7. Give two difference between Hormones and vitamins

8. Write a note on denaturation of proteins

9. What are reducing and non – reducing sugars?

10.Why carbohydrates are generally optically active.

16.Write the structure of α-D (+) glucophyranose

17.What are different types of RNA which are found in cell

18.Write a note on formation of α-helix .

19.What are the functions of lipids in living organism.

Unit 15 CHEMISTRY IN 

EVERYDAY LIFE

1. What are antibiotics?

2. Name one substance which can act as both analgesic and antiphyretic

3. Write a note on synthetic detergents

4. How do antiseptics differ from disinfectants?

5. What are food preservatives?

6. What are drugs? How are they classified

7. How the tranquilizers work in body.

8. Write the structural formula of aspirin.

9. Explain the mechanism of cleansing action of soaps and detergents

10. Which sweetening agent are used to prepare sweets for a diabetic patient?

11. What are narcotic and non – narcotic drugs. Give examples

12. What are anti fertility drugs? Give examples.

13. Write a note on co –polymer

14. What are bio degradable polymers? Give examples.

15. How is terylene prepared?

16. Write a note on vulcanization of rubber