CHSE CHEMISTRY PREVIOUS YEAR QUESTION PAPER

Chse chemistry previous 10 year questions

2018 to 2008:Download

Previous year questions are very important to solve it gives Idea about which type of Questions are coming on exam . solving all these previous year questions are enough to score above 80%

Here some chapter wise short questions for practice purpose

SOLID STATE

1. Name the most symmetrical crystal system.

Ans. Cubic crystal system (a=b=c )is most symmetrical crystal system.

2. How is unit cell related to space lattice?

Ans. Space lattice is obtained by repeating ne

unit cell in three dimensions.

3.How many crystal systems are there?

Ans. Seven crystal systems.

4.How many Bravais lattices are there ?

Ans. 14 Bravais lattices.

5. How many atoms are present per unit cell of:

(i) simple cubic

(ii) body-centred cubic and

(iii) face-centred cubic

Ans. (i) 1, (ii) 2, (iii)4

6.Give the relationship between nearest neighbour distance (d) and radius (r) of an atom with edge length (a) of body-centred cubic system.

Ans. i) d =a (i)r= a

7.What is the coordination number of an atom in Two dimensional square close packing (scp)?

Ans. 4

8. What is the coordination number in hcp and ccp ?

Ans. 12, in both hcp and ccp.

9.Howmany atoms are present per unit cell in a hcp structure?

Ans. 6

10.What is vacancy defect?

Ans. When lattice sites are vacant, the crystal is said to have vacancy defect.

11. Which crystal defect does not affect the density of solid ?

Ans. Frenkel defect.

12. Name one ionic solid, which shows both Frenkel defect and Schottky defects.

Ans. AgBr.

13. Name one salt which is added to AgCl so as to produce cation vacancies.

Ans. CdCl

14.What is the effect of the presence of Schottky defect on the density of a crystal ?

Ans. Density decreases.

Solution

1.What is the molarity of 1.5 N HNO ?

Ans. 1.5 M.

2.What are the units of molality '?

Ans. mol kg-¹

3.Write the units of molarity.

Ans. mol L-¹

4.What is the molality of a solution containing mol of solute dissolved in 5 kg of solvent ?

Ans. 0.2 ÷5 = 0.04 m

5.Which law gives the relationship between the mass (m) of the gas dissolved in a given volume of liquid at a constant temperature and the pressure (p) of the gas.

Ans. Henry's law ( m = kp)

6.What is the effect of pressure on the solubility of exhibits a gas ?

Ans. Solubility of gases increases with increage exhibits of pressure.

7. What is the efect of temperature on the solubility,if the substance dissolves in water with liberation anisotropy ?of heat ?

Ans. Solubility decreases with rise in temperature exhibition.

8. Between hydrogen and helium which is moreby soluble in water ?

Ans. Hydrogen.

9, Between hydrogen and helium which one has better higher value of Henry's law constant ?

Ans. Helium.

10.What is the effect of pressure on the solubility of a solid in liquid ?

Ans. Very small and insignificant

11. What is the term assigned to the pressure exerted by the vapours on the surface of liquid in equilibrium at a given temperature ?

Ans. Vapour pressure.

12. What is the term assigned to the solutions, which obey Raoult's law over entire range of concentration ?

Ans. Ideal solutions.

ELECTROCHEMISTRY

1.Give examples of weak electrolytes.

Ans. CH3COOH, H2CO3, NH4OH, AgCl etc.

2.Give examples of strong electrolytes.

Ans. NaCI, HNO3, HCIO4, NaOH etc.

3.How conductivity of semiconductor varies with temperature ?

Ans. Conductivity increases with increase in

temperature.

4.What is charge carried by one mole of electrons ?

Ans. One mole of electron carry 96500 coulombs or one faraday.

5. How electrochemical equivalent is related to chemical equivalent ?

Ans. E =96500 x Z

where E = chemical equivalent

Z= electrochemical equivalent

6.What will be formed at cathode when aqueous solution of NaCl is electrolysed ?

Ans. Hydrogen gas is obtained at cathode.

7.What is the electrolyte in lead storage battery ?

Ans. 30% of H2SO4

8.What is the value of one faraday ?

Ans. IF =96500C/mol

9.What is the voltage of standard state reduction of H at 25°C?

Ans. ZERO volt

10.Write unit of equivalent conductance.

Ans. ohm-¹ cm² eq-¹

11. Write unit of specific conductance.

Ans. S cm-¹

12.What is unit of molar conductivity or molar conductance ?

Ans. ohm-¹ cm² mol-¹

13. Write the unit of cell constant.

Ans. cm-¹

14. If a silver spoon is to be electroplated, whether it is anode or cathode ?

Ans. Cathode

15.Give example of fuel cells.

Ans. Hydrogen - oxygen fuel cell.

Metallurgy

1.Which is better reducing agent as 983 K, C or CO2 ?

Ans. Carbon.

2.Which is the cheapest and most abundant reducing agent used in the extraction of metals?

Ans. Carbon in the form of coke

3.Namehe method used for the refining of Nickel Na metal.

Ans. Mond's process.

4.Name the method used for refining of copper metal.

Ans. Electrolytic refining

5.Name two ores of copper.

Ans. Copper glance (CuS), cuprite (CuO)

6.Between zinc and copper which metal will react with dilute sulphuric acid ?

Ans. Zinc

7.Name the process by which sulphide ore is

concentrated ?

Ans. Roasting

8.Brass contains which metals ?

Ans. Copper and Zine

9.Write the composition of German Silver.

Name any two alloys of steel.

Ans. Cu, Zn and Ni

10.Name two ores of iron.

Ans. Stainless steel, chrome Steel.

11.Name two alloys of copper

Ans. Haematite, Magnetite

Biomolecules

1 Which acts as control house of the cell ?

Ans. Nucleus.

2.Which one represents the energy currency of the cell ?

Ans. ATP

3.Which organelles are known as power house of the cell ?

Ans. Mitochondria

4.Which organelle is called export house of the cell ?

Ans. Golgi apparatus

5.What is the mass % of water in cell ?

Ans. Approximately 70%

6.Which biomolecule is most abundant in cell ?

Ans, Protein (~15% by mass)

7.Which molecule acts as centre of all cellular activities through energy cycle?

Ans. Adenosine triphosphate (ATP)

8. Name two reducing sugars.

Ans. Glucose and fructose

9.what is common name of lactose ?

Ans. Milk sugar

10.give one example of transport proteins.

Ans. Halmogloblin

POLYMERS

1.Write two ueses of bakelite?

Ans. It is used for making electrical goods,

fountain pen, plywood, combs etc.

2.What is Teflon ? Write some of its uses.

Ans. It is a polymer of tetra - fluroethylene.

It is used in non- stick cooking utensils and

also insulator for making valves.

3.Define thermoplastic.

Ans. A plast which softens on heatin is called thermoplastic.

For example: PVC. Polythene .

4.Write one use of neoprene

Ans. It is used in shoe - heals.

5. What is neoprene?

Ans. It is a synthetic rubber and its monomer is chloroprene.

6 Write some uses of Buna -S.

Ans. It is used for automobiles tyres, rubber shoes,belts etc.

7. How teflon is prepared ?

Ans. It is prepared by heating etrafluroethylene.in presence of ammonium persulphate.

8. Write monomer of teflon.

Ans. C.F (tetrafluoroethylene).

9. Give some examples of natural polymers.

Ans. i) Rubber (ii) Cellulose (ii) Starch (iv) Wool(V) Silk.

10. What is the monomer of natural rubber?

Ans. Isoprene.

11. Write name of synthetic polymers.

Ans. (i) PVC (ii) Terylene (iii) Nylon

12. Write uses of decron.

Ans. It is used to make fibres.

13. What is orion?

Ans. It is polymer of acrylonitrile.

CHEMISTRY IN EVERYDAY LIFE

1. Write some names of antibiotics.

Ans. i) Pencillin

ii)Tetracycline

(iii) Streptomycin

iv) Ampicilline

2.What is the origin of antibiotic ?

Ans. Antibiotics are of microbial origin

3.Name the process for manufacture of soap.

Ans. Saponification.

4.Why detergents are better in hand water than Soap ?

Ans. Because detergents do not form any scum in hard water due to solubility of their Mg and Ca salts,which are usually present in hard water, But soap forms scum with Ca and Mg ions as they are insoluble.

5. What are fillers?

Ans. It increases the weight or make the soap

fatty bulky.

For example: talc, starch, pearl ash, glauber salt benzene etc.

6. What are hard and soft soap ?

Ans. (i) Soap derived from fats and caustic soda are known as hard soap. Uses: For washing purposes.

(ii)Soap derived from fat and caustic potash are acid knownas soft soap.

Uses: Used as bath soap.

7.What is action of neem oil ?

Ans. Used as disinfectant

8. What is neat soap ?

Ans. Soap which is free from fillers, colours, scent or perfumes manufactured by hydrolysis of oil and fats by alkalies.

9. Write the name of different types of detergents

Ans. (1) Anionic detergents

(2) Cationic detergents

(3) Amphoteric detergents

(4) Non-ionic detergents

10. Which is a common detergent ?

Ans. Sodium alkylbenzene Sulphonates

11. What is cationic detergent?

Ans. Its detergent property is due to the presence of cations in solution.

12.Why sodium silicate is used in making laundry soap ?

Ans. To inerease the cleaning capacity of ordinary Soap.

13.Define "Soaps"

Ans. Soap is a sodium or potassium salt of higher fatty acids such as oleic, stearic, lauric, palmitic acids.

14. Define "detergent"

Ans. Detergents are sodium salts of long chain salt benzene sulphonic acid and long chain alkyl hydrogen sulphate

15. What are the differences between soft and hard soda Soap

Ans.(i) Soft soap is potassium salt of higher fatty purposes.

acid while hard soft is sodium salt of higher are fatty acids

(ii) Hard soap is moderately soluble in water while soft soap is easily soluble in water.

iii) Cleansing action of soft soap is better than hard soap.