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Delhi Public School, Kurukshetra

Summer Holiday 2019-20

Class-XII Dear Students,

Summer Vacations is a welcome break…… Break from fixed schedule, rules and regulations of school,

Freedom brings more responsibility, keeping this in mind, we have planned most of the activities for you to keep

you engaged positively and your energies well directed. Though teachers will not be physically present to keep a

supervisory eye on you and your work. Guardian Angles at home i.e.your dear mama and papa are there to take

care of your emotional, social, physical & academic needs.

We hope your home work and activities will be well managed and presented so that all of you earn a golden star

as a grade .

We wish you a wonderful time ahead!

Good habits and Good manners are life long assets and manners must be practiced until they become a habit.

Four magic words that are basics of good manners are- Please , Thank you, Excuse me and sorry . Make these

four words a habit and see the difference.

Manners

At home:

Help to keep the house clean especially the areas you us. Clear the toys, books or craft that

remain after you have finished.

Honesty is the best policy. Tell the truth at all times.

Be polite

Share the T.V time. Do not sit too close while watching T.V.

Be fair with your friends, brothers and sisters .

Be responsible

At the dining table:

Take small helping and refill, clean your plate up.

Take small bites, eat neatly, slowly with your mouth closed.

Help to clear the table and clean up.

In the Park:

Littering makes the park untidy.

Destroying the plants or plucking the flowers will spoil the beauty.

Wait for your turn on swing and slides.

At a Party:

Wish the host.

Don’t mess up somebody’s house.

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While shopping:

Softly ask your parent for what you want. If refused, don’t throw a tantrum.

Be careful, don’t touch any breakable item.

On the telephone:

If there are no elders around, don’t let the phone ring long, answer it.

Talk softly when someone is speaking on the phone and don’t interrupt.

Hygiene

Brush your teeth twice a day.

Do trim your nails often.

Do not waste water and electricity.

Keep your surrounding and environment clean. It is bad habit to throw things out of the window,

car or a balcony.

Make friends having good habits who respect their elders and use good language.

English:-

Pick five unseen passages from any english newspaper, frame ten questions for the same and

answer them (attach the reference passages in your notebook.)

Draft five Advertisements, each for 'Situation Vacant' and 'Sale and Purchase' columns.

Write any three Articles on:-

1.Election in Democracy

2.No nation can rise above the level of its teacher.

3.Social Media- a boon or bane.

Revise the Literature part that has already been done in the classes.

The students will conduct and shoot three INTERVIEWS of the celebrities/VIP of their city.(Any

educationist, lawyer, businessman, player, bureaucrats etc.)

Questionnaire :-

*Minimum three questions on childhood

*Three questions on education

*Three questions on profession

*Three questions on personal/family life

*One question for future plan.

*Their message for students

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Physics:-General Instruction :

1. A copy of this assignment should be pasted in the Holiday Home-work register.

2. All the questions should be solved in Holiday Home-work register only.

1. A free pith-ball A of 8 g carries a positive charge of 5 x 10 -8 C. What must be the nature

and magnitude of charge that should be given to a second pith-ball B fixed at 5 cm below

the former ball so that the upper ball is stationery?

2.Two fixed point charges +4e and +e units are separated by a distance a. where should the

third point charge be placed for it to be in equilibrium?

3. Derive an expression of electric field intensity at a point on equatorial axis of an electric

dipole.

4.Show that the force on each plate of a capacitor has a magnitude equal to QE/2, where Q is

the charge on the capacitor and E is the magnitude of the electric field between the plates

of the capacitor. Explain the origin of factor ½.

5.Two small spheres each of mass “m” kg and charge q coulomb are suspended from a point By insulating threads each of l metre length, but of negligible mass. If Ѳ is the angle which each string makes with the verticle when equilibrium has been reached, show that q2=4mgl 2sin 2ѲtanѲ (4πϵ0) 7.Two small charged spheres contain charges +q1 and +q2 respectively. A charge dq is removed from sphere containing charge q1 and is transferred to the other. Find the charge on each sphere for maximum electric force between them. 8.Two-point charges +q and -2q are placed at the vertices B and C of an equilateral triangle

ABC of side a. obtain the expression for magnitude and direction of resultant electric force

at the vertex A due to these two charges.

9..A pendulum bob of mass 80 milligram and carrying a charge of 2 × 10-8C is at rest in a

horizontal uniform electric field of 2×10 4 Vm-1. Find the tension in the thread of the

pendulum and the angle it makes with the vertical. What are the magnitude and direction

of electric field at centre of the square, if q=1.0×10 -8C and a=5cm

10.State Gauss’s Theorem in electrostatics. Using this theorem derive an expression of electric

field intensity due to a line charge.

11. (a) Define electric flux .Write its SI units.

(b) Using Gauss’s law , prove that the electric field at a point due to a uniformly charges

infinite plane sheet is independent of the distance from it.

12..Obtain the formula for the electric field due to a long thin wire of uniform linear charge

density λ without using Gauss’s law. *Hint: use coulombs’ law directly and evaluate

necessary integral.].

13.Can a metal sphere of radius 1 cm hold a charge of 1 coulomb? Justify your answer ?

14. Is the electrostatic potential necessarily zero at a point where the electric field strength is

zero ? Give an example to illustrate your answer

15.Derive an expression for the energy stored in a parallel plate capacitor

16.Define the term polarisation of a dielectric medium. Write its S.I unit

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17. Work done by an electrostatic field is independent of the path followed between two

points. Justify

Q2. Revise unit -1(Electrostatics) of your Book.

Q3. Investigatory Project based on any topic of Physics.

(Chart of the project and file of the project)

Q4. Do20 numericals based on the following topic in your Holiday Home-work Register.

1. Coulomb’s Law

2. Electric Field

3. Capacitance

Biology:-

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Chemistry:-

Class XII Assignment(Chemistry)

Solutions

1. State Henry’s Law. What are the applications of Henry’s Law? 2. What factors affect the solubility of gas in a liquid?

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3. State Raoult’s law for a binary solution containing volatile components. 4. Define an ideal solution. State the characteristics of ideal solution. 5. What type of solution is formed by mixing equal volumes of n- hexane and n-heptane or bromoethane and

chloroethane or benzene and toluene? Explain. 6. What are non ideal solutions? Give examples. 7. Give one example each of miscible pairs showing positive and negative deviations from Raoult’s Law. Give

reasons for such deviations. (or) Explain with a suitable diagram and appropriate examples why some non ideal solutions show positive deviation from ideal behaviour.(or)What are non ideal solutions?

8. What role does intermolecular interaction play in deciding the vapour pressure of solutions (i) alcohol and acetone (ii) chloroform and acetone. (or) Draw a suitable diagram to express the relationship of ideal solutions of A and B between vapour pressures and mole fractions of components at constant temperature.

9. What are azoetropes? Classify them with examples. 10. What do you understand by colligative properties? 11. How is relative lowering of vapour pressure defined for a solution containing a volatile solvent and a non volatile

solute? How is this function related to mole fraction of the solute and the solvent? (or)What is relative lowering of vapour pressure? Derive an expression for it. How is it useful in determining molecular mass of solute?

12. The solution of a non volatile solute boils at a higher temperature than the pure solvent. Show this relationship on a graphic diagram. (or) Why is the boiling point of solvent elevated when a non volatile solute is added to it?

13. With the help of a neat diagram, indicate why the solution of a non volatile solute should freeze at a temperature lower than the freezing point of the pure solvent? (or) Why is the freezing point of a solvent be depressed when a non volatile solute is added to it?

14. How can you say that osmotic pressure is a colligative property? How can it be used to determine the molecular mass of a non volatile solute?

15. What is meant by abnormal molecular mass of solute? Discuss the factors which bring abnormality in the experimentally determined molecular masses of solutes using colligative properties.

16. What is Van’t Hoff factor? 17. Define the following terms. Mass percentage, Mass percentage, Mass by volume percentage, Parts per million,

Mole fraction, Molarity, Molality. 18. What are isotonic solutions? 19. Define the term solution. How many types of solutions are formed? Write briefly about each type with an

example. 20. Suppose a solid solution is formed between two substances, one whose particles are very large and the other

whose particles are very small. What kind of solid solution is this likely to be? 21. What role does the molecular interaction play in a solution of alcohol and water? 22. Why do gases always tend to be less soluble in liquids as the temperature is raised? 23. Suggest the most important type of intermolecular attractive interaction in the following pairs.

a. n-hexane and n-octane (ii) I2 and CCl4 (iii) NaClO4 and water (iv) methanol and acetone (v) acetonitrile (CH3CN) and acetone (C3H6O).

24. Based on solute-solvent interactions, arrange the following in order of increasing solubility in n-octane and explain. Cyclohexane, KCl, CH3OH, CH3CN.

25. Amongst the following compounds, identify which are insoluble, partially soluble and highly soluble in water? (i) phenol (ii) toluene (iii) formic acid (iv) ethylene glycol (v) chloroform (vi) pentanol.

26. What are the advantages of using Osmotic property to determine molecular mass of solids over other colligative properties?

27. What do you mean by boiling point elevation constant (ebulloscopic constant) and freezing point depression constant (cryoscopic constant) for a solvent.

28. What is the effect of temperature on molality and molarity? Concept Based Questions

1. Why does molality of a solution remain unchanged with temperature while molarity changes? (or) Why is it advantageous to use molality over molarity?

2. Two liquids boil at 145°C and 190° respectively. Which one has a higher vapour pressure at 80°C?

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3. What would be the Van’t Hoff factor of K3[Fe(CN)6] , K2SO4 , K4[Fe(CN)6], Mg SO4, NaCl, KCl? 4. O f 0.1 molal solutions of glucose and sodium chloride respectively, which one will have a higher boiling point 5. A and B on mixing produced a warm solution. What type of deviation is there and why? (or) Why is an increase in

temperature observed on chloroform and acetone. 6. When 30 ml of ethyl alcohol and 30 ml of water are mixed, the volume of resulting solution is more than 60 ml.

Explain. 7. 10 ml of liquid A was mixed with 10ml of liquid B. The volume of the resulting solution was found to be 19.9 ml.

What would you conclude? 8. A and B on mixing produced a colder solution. What type of deviation is there and why? 9. Why is the elevation of boiling point of water different in 0.1 molar NaCl solution and 0.1 molar sugar solution? 10. Which will have higher boiling point, 0.1M NaCl or 0.1M BaCl2? 11. Solution A is obtained by dissolving 1g of glucose in 100g of water and solution B by dissolving 1 g of urea in 100g

of water. Which will have a higher boiling point and why? 12. Why is cooking temperature in a pressure cooker higher than in a open pan? 13. When is the value of Van’t Hoff factor greater than 1 and less than 1? 14. In determination of molar mass of A+B-, using colligative property, what may be the value of Van’t Hoff factor if the

solute is 50% dissociated? 15. Give an example of a compound in which hydrogen bonding results in form of dimer? 16. Give an example of a solution containing a solid in solid solvent. 17. What is anti freeze? (or) Why is it advised to add ethylene glycol in a car radiator while driving in hill station? 18. What is de- icing agent? Sodium chloride or calcium chloride is used to clear snow from roads. Why? 19. What happens when RBCs are placed in

a) 1% NaCl solution b) 0.5% NaCl solution

20. What happens when blood cells are placed in pure water?

21. Which has the highest freezing point? i) 1 M glucose b) 1 M NaCl c) 1 M CaCl2 d) 1 M AlF3

22.) 3.9 g of benzoic acid dissolved in 4.9g of benzene shows a depression in freezing point of 1.62K. Calculate the

Van’t Hoff factor and predict the nature of solute (associated or dissociated).

Q23. Calculate the mass of NaCl to be dissolved in 37.2 gm of water to lower the freezing point by20C,assuming that

NaCl undergoes complete dissociation (Kffor water=1.86 KKg/mol)

Q24.Some ethylene glycol(HOCH2CH2OH)is added your cars cooling system along with 5 Kg of water. If the freezing

point of water glycolsolution is -150c, What is the boiling point of the the solution?(Kb=0.52KKg/mol and

Kf=1.86KKg/mol for water)

Q25.Determine the osmotic pressure of a solution prepared by dissolving 2.5 x 10-2g of K2SO4in 2L of water at

250C,assuming that it is completely dissociated.(R=0.0821 Latm K-1mol-1,molarmass)

Q26.Calculate the freezing point of solution containing 60 g of glucose(Molar mass=180 g mol-1)in 250 g of water.

(kfof water= 1.86 K kg mol-

Numericals:

16. When 20g of naptholic acid (C11H8O2) is dissolved in 50g of benzene (Kf = 1.72KKg/mol) a freezing point depression

of 2K is observed. The van’t Hoff factor is

a) 0.5 b) 1 c) 2 d) 3

17. Vapour pressure of water at 20˚C is 17.5 mm Hg. If 18 g of glucose is addded to 178.2g of water at 20˚C, the vpou

pressure of the resulting solution will be

a) 17,325 mm Hg b) 17.675mm Hg c) 15.75mm Hg d) 16.5mmHg

18. Two liquids X nd Y form ideal solutions. The mixture has a vapour presssure of 400mm at 300K when mixwd in the

molar ratio of 1:1 and a vapour pressure of 350mm of Hg when mixwd in the molar ratio of 1:2 at the same

temperature. The vapou pressure of two pure liquids are

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a) 250 mm, 550mm b) 350mm , 450mm c) 550mm. 700mm d) 550mm, 500mm e) 550mm. 250mm

19. A binary solution is prepared by mixig n- heptane an ethanol. Which statement is true regarding the behaviour of

the solution.

a) The solution is an ideal solution b) The solution is non ideal showing poitive deviation from Raoult’s law. c) The

solution is non ideal showing negative deviation from Raoult’s law d) n-heptane shows positive deviation while

ethanol shows negative deviation from Raoult’s law

20. Two liquids X and Y form an ideal solution. At 300 K vapour presssure of a solution containing 1 mol of X nd 3 mol

of Y is 550 mm Hg. At the same teperature,, if 1mol of Y is futher added to the solution, vapour presssure

increases by 10 mm Hg. Vapou pressure in mm Hg of X and Y in the pure state will be

a) 200 , 300 b) 300, 400 c) 400, 600 d) 500, 600.

21. The Henry’s Law constant for solubility of N2 gas in water at 298K is 1x 105 atm. The mole fraction of N2 in air is 0.8.

The number of moles of N2 from air dissolved in 10 moles of water at 298 K and 5 atm pressure is

a) 4x 10-4 b) 4x 10-5 c) 5 x 10-4 d) 4x 10-6

22.. If sodiumsulphate is consiered to be completely dissociated into cations and anions in aqueous solution, the

change in freezing point of water, when 0.01 mol of sodium sulphate is dissolved in 1 Kg of water (Kf = 1.86

KKg/mol)

a) 0.0744 K b) 0.0186 K c) 0.0372 K d) 0.0558 K

23. On mixing heptane and octane they form an ideal solution at 373 K the vapour pressures of heptane and octane

are 105 kPa and 45 kPa respectively. Vapour pressure of the solution obtained by mixing 25g heptane and 35g of

octane will be

a) 96.2 kPa b) 144.5 kPa c) 72 kPa d) 36.1 kPa

24. An aqueous solution is 1.00 molal in KI. Which change will cause vapour pressure of solution to increase?

a) Addition of NaCl b) Addition of sodium sulphate c) Addition o 1.00 molal KI d) Addition of water

25. A solution of sucrose(342g/mol) has been prepared by dissolving 68.5 g of sucrose in 1000 g of water. The freezing

point of the solution will be (Kf = 1.86 KKg/mol)

a) -0.372˚C b) -0.52˚C c) 0.3772 ˚C d) -0.57 ˚C

Numericals

1. A solution to be used in hand lotion is made by mixing 90.0g of water, 9.2g of ethyl alcohol and and 18.4g of glycerol ( C3H8O3). Calculate the mole fraction of glycerol present in it. (0.037)

2. The density of 10% by mass of KCl solution is 1.06g/cc. Calculate molarity of the solution. ( 1.42M) 3. Find the molarity of the solution obtained by miximg 100mL of 0.3M H2SO4 and 200mL of 1.5M H2SO4 (1.1M) 4. What volume of 96% of H2SO4 solution (density = 1.83g/mL) is required to make 4 litres of 3M H2SO4? (669 mL of

diluted to 4 litres). 5. Methanol and ethanol form nearly an ideal solution at 300K. A solution is made by mixing 32g methanol and 23g

ethanol. Calculate the partial pressures of the components and total vapour pressure of solution at 300K. (90 mmHg, 17mmHg, 77mm Hg)

6. Vapou pressures of pure benzene and toluene at 293 K is 75mm Hg and 22 mm Hg repecively. 7. . Vapour pressure of pure benzene and toluene at 293 K is 75 mm Hg and 22 mm Hg respectively. 23.4 g of

benzene and 64.4 g of toluene are mixed. If the two form an ideal solution, calculate the mole fraction of benzene in the vapour phase assuming that the vapours are in equilibrium with the liquid mixture at this temperature. (0.59)

8. 18.2 g of urea is dissolved in 100g of water at 50ºC. The lowering of vapour pressure produced is 5mm Hg. Calculate the molecular mass of urea. The vapour pressure of water at 50ºC is 92 mm Hg. (57.05)

9. 8. The vapour pressure of dilute aqueous solution of glucose is 750 mm Hg. Calculate (i)molality (ii) mole fraction of solute. (0.74m ; 0.0132)

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10. The boiling point of water becomes becomes 100.52 50ºC. If 1.5 g of a non volatile solute is dissolved in 100 mL of it. Calculate the molecular mass of the solute. (Kb = 0.6k/m ) (17.3)

11. 10 g of a non volatile solute when dissolved in 100g of benzene raises its boiling point by 1ºC. What is the molecular mass of the solute? (253)

12. The osmotic pressure of a dilute aqueous solution of a compound X containg 0.12g per litre is twice the osmotic pressure of a dilute aqueous solution of another compound Y containing 0.18g per litre. What is the ratio of the molecular mass of X to Y if both remain in molecular form in solution? (1:3)

13. 1 liter aqueous solution of sucrose weighing 1015 g has an osmotic pressure of 4.82 atm at 293 K. What is the molality of sucrose solution? (0.2112m)

14. Assuming completeionisation, calculate the expected freezing point of solton prepared by adding Glauber’s salt Na2SO4.10H2O in 0.1Kg of water? Kf = 1.86 K Kg/mol. (271.95)

15. A solution contains 7.45 KCl per litre of the solution, It has an osmotic pressure of 4.68 atm at 300 K. Calculate the degree of dissociation of KCl in this solution. (90%)

16. Calculate the Van’t Hoff factor of CdSO4 (mol. Mass = 208.4) if the dissociation of 5.21 g of it in half liter of water gives a depression in freezing point of 0.168ºC (Kf = 1.86 K Kg/mol.) (1.806)

17. A solution of sucrose has been prepared by dissolving 68.4 g of sucrose in 1 Kg of water. Calculate i) Vapou pressure of the solution at 198 K ii) osmotic pressure of solution at 298 K iii) freezing point of the solution. (Kf = 1.86 K Kg/mol.) (0.-239 atm, 4.887 atm -0.372 ºC)

18. Calculate the amount of ethlene glycol to be added to 4 Kg of water to prevent it from freezing at -6 ºC ( 804.32) 19. The freezing point of a solution containing 0.3g of acetic acid in 30.0 g of benzene is lowered by 0.45 ºC. Calculate

van’t Hoff factor.( Kf = 5.12 K Kg/mol.) ( 20. How much urea should be dissolved in 50g of water so that the vapour pressure at room temperature is reduced

to 25%. Calculte molality of solution obtained. (55.56g: 18.2) 21. An aqueous solutin containing 1.24 g of barium chloride in 100g of water boils at 100.0832 ºC. Calculte the degree

of dissociaton of barium chloride. (Kb = 0.52 K Kg/mol) (0.835) 22. The osmotic pressure of 0.013 molar solution of an electrolyte is found to be 0.70 atm at 27 ºC. Calcolate the van’t

Hoff factor. (2.76) 23. 2g of C6H5COOH dissolved in 25g of benzene shows a depression in freezing point equal to 1.62 K. What is the

percentage association if it exists as a dimer? (Kb = 4.9 K Kg/mol) (99.2%) 24. 45 g of ethylene glycol C2H6O2 is mixed with 600g of water. Calculate i) Freezing point depression ii) freezing

point of the solution. Kf = 1.86 K Kg/mol (2.25 ºC : -2.25 ºC) 25. Find the amount of 98% pure Na2CO3 required to prepare 5 litres of 2N solution. ( 540.8g)

Board Questions

2011

1. State the following (2) a) Raoult’s Law in its general form in reference to solutions b) Henry’s law about partial pressure of a gas in a mixture.

2. A solution prepared by dissolving 8.95 mg of a gene fragment in 35.0 mL of water has an osmotic pressure of 0.335 torr at 25˚C. Assuming that the gene fragment is a non electrolyte, calculate the molar mass?

Class XII Assignment

Electrochemistry Assignment

1. Differentiate between Galvanic cell and electrolytic cell

2. How would you determine the standard electrode potential of the system Mg2+|Mg

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3. Depict the galvanic cell in which the reaction takes place. Further show:

(i) Which of the electrode is negatively charged? (ii) The carriers of the current in the cell. (iii) Individual

reaction at each electrode.

4. How is electrode potential different from cell potential?

5. Describe the construction and working of standard hydrogen electrode.

6. What is the purpose of salt bridge placed between two half cells of a galvanic cell? 7. Give the representation of the Daniel cell. 8. Define resistivity and conductivity.

9. What is cell constant? How is it determined? 10. What are the problems faced in measuring R of ionic solutions and how are they overcome

11.Differentiate between metallic and electrolytic conduction.

12. Define the terms conductivity and molar conductivity for solution of an electrolyte. Discuss their variation with

concentration.

13. What is the unit of molar conductivity?

14. What is limiting molar conductivity?

15. Describe the characteristics of variation of molar conductivity with dilution for a) strong electrolyte b) weak

electrolyte. (or)

With the help of a graph explain why it is not possible to determine the limiting molar

conductivity for a weak electrolyte by extrapolating the concentration-molar conductance

curve as for strong electrolytes. (or) Express the relationship between degree of dissociation of an

electrolyte and its molar conductivities.

16. How is molar conductivity of a weak electrolyte at infinite dilution determined? (or) State

Kohlrausch’s Law. Write two applications.

17. How will you determine Λm0 for water

18. State Faraday’s Laws of Electrolysis.

19. What is the difference between primary cell and secondary cell?

20. Describe the Lechlanche cell with reference to electrodes used and reactions occurring at

electrodes.

21. Describe the composition of anode and cathode in mercury cell. Write the electrode reactions

22. Write the cell reactions which occur in lead storage battery when battery is in use and when it is on charging

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23. What is the reaction taking place in Nickel cadmium cell?

24. What are fuel cells? Suggest two materials other than hydrogen that can be used as fuels in fuel cell.

25. Describe the hydrogen fuel cell. 26. Rusting is an electrochemical process. Explain.

27. How can corrosion be prevented?

28. Account for the following

a) Rusting of iron is quicker in saline water than in ordinary water. b) Alkaline medium inhibits the rusting of

iron. c) Iron does not rust even if zinc coating is broken in a galvanized iron pipe.

29. Predict the products of electrolysis in each of the following:

(i) An aqueous solution of AgNO3 with silver electrodes. (ii) An aqueous solution of AgNO3 with platinum

electrodes. (iii) A dilute solution of H2SO4 with platinum electrodes. (iv) An aqueous solution of CuCl2 with

platinum electrodes.

30. Standard reduction potentials are given below

F2/F- = +2.9V, Ag+/Ag = - 0.8V, Cu+/Cu = +0.5V Fe2+/Fe = -0.4V, Na+/Na= -2.7V ,

K+/K= -2.9V

a) Arrange oxidizing agents in order of increasing strength b) Which will oxidize Cu to Cu+under

standard conditions

31. Can you store copper sulphate solutions in a zinc pot? 32. Given the standard electrode potentials,

Arrange these metals in their increasing order of reducing power.

33. Arrange the following metals in the order in which they displace each other from the solution of their salts. Al, Cu, Fe, Mg and Zn.

34. Why is it necessary to platinize the electrodes of a conductivity cell before it is used for conductance measurement?

35. Suggest a list of metals that are extracted electrolytically. EXTRA

1. Define the term – standard electrode potential?

2.What is electromotive force of a cell?

3. Can an electrochemical cell act as electrolytic cell? How?

4. Single electrode potential cannot be determined. Why?

5. What is an electrochemical series? How does it predict the feasibility of a certain redox reaction?

6. Give some uses of electrochemical cells?

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7. What is meant by Faraday’s constant?

8. A Leclanche cell is also called dry cell. Why?

9. Why is the voltage of a mercury cell constant during its working?

10. Name two metals than can be used for cathodic protection of iron

Numericals for Practice

1. The conductivity of an aq. Solution of NaCl in a cell is 92 x 10-4 ohm-1cm-1. The resistance offered by the cell is 247.8ohm. Calculate the cell constant for the cell. (2.28/cm)

2. The conductivity of a solution containing 1g of anhydrous BaCl2 in 200cm3 of the solution is found to be 0.0058S/cm. Calculate the molar conductivity of the solution. (λm = 241.28Scm2/)

3. The resistance of a 0.01M solution of KCl is 100Ω at 298 K. Calculate (1) conductance (ii) conductivity (iii) resistivity (10-2, 10-2, 100) G* = 1cm-1

4. 0.5 molar solution of a salt placed between platinum electrodes 2 cm apart and each of area of cross section 4cm2 has a resistance of 25Ω. Calculate λm. (40)

5. Calculate the molar conductivity at infinite dilution of AgCl from the following data. Λom AgNO3 = 133.4, ΛomKCl = 149.9, Λom KNO3 = 144.9 Scm2/mol (138.45 Scm2/mol)

6. The conductivity of 0.001 M acetic acid is 4.95 X 10-5 S/cm. Calculate the dissociation constant. Λom = 90.5 Scm2/mol. (1.85x10-5-)

7. At 18 ºC, the conductivities at infinite dilution of NH4Cl, NaOH and NaCl are 129.8, 217.4 and 108.9 Scm2/mol. If the equivalent conductivity of n/100 solution of NH4OH is 9.93 Scm2/eq, Calculate the degree of dissociation and dissociation constant at this dilution. (4.17%, 1.8x10-5 )

8. Construct the cells in which the following reactions are taking place. Which of the electrodes act as anode and which as cathode? i) Zn + CuSO4 →ZnSO4 + Cu ii) Cu + 2AgNO3 → Cu(NO3)2 + 2Ag iii) Zn + H2SO4 →ZnSO4 + H2 iv) Fe

+ SnCl2 → FeCl2 + Sn

9. Calculate the electrode potential at a copper electrode dipped in a 0.1 M solution of copper sulphate at

25ºC. The standard electrode potential of Cu2+/Cu system is 0.34 V (0.31V)

10. What is a single electrode potential of a half cell for zinc electrode dipping in 0.01M zincsulphate solution

at 25ºC.The standard electrode potential of Zn/Zn2+ system is 0.763 V. (0.8221V)

11. Calculate the emf of the cell. Mg/Mg2+(1M)||Ag+ (0.001M)|Ag EºAg+/Ag = 0.8V ; |EºMg2+/Mg = -237V.

What will be the effect on emf if concentration of Mg2+ is decreased to 0.1M? (3.013V; 3.022V)

12. To find the standard potential of M3+/M electrode, the following cell is constituted. Pt|

M/M3+(0.00018M)||Ag+ (0.01M)|Ag. The emf of this cell is found to be 0.42V. Calculate the standard

potential of the half reaction M3+ +3e-→M EºAg+/Ag = 0.8V (0.32V)

13. A zinc rod is dipped in 0.1M solution of ZnSO4. The salt is 95% dissociated at this dilution at 298 K.

Calculate the electrode potential given that EºZn2+/Zn = -0.76V ( -0.79V)

14. One half in a voltaic cell is constructed from a silver wire dipped in silver nitrate solution of unknown

concentration. The other half cell of zinc electrode in 0.10M solution of Zn(NO)3. A voltage of 1.48 is

measured for this cell. Use this information to calculate theconcentration of silver nitrate solution.

EºZn2+/Zn = -0.763V; EºAg+/Ag = 0.8V (0.0124M)

15. Calculate the pH of the half cell Pt(H2)1atm/H2SO4, its oxidation potential is 0.4V (6.77)

16. Calculate the cell potential of the following concentration cell . PtH2(2atm)|H+(0.M)||H+ (0.3M)| H2(4atm)

(0.019V)

13

17. For the reaction Ni/Ni2+||Ag+ |Ag EºNi2+/Ni = -0.25V; EºAg+/Ag = 0.8V. Calculate the equilibrium constant

at 25ºC. How much maximum work can be obtained by the operation of the cell? (3.98 x 1035, 202650J)

18.Estimate the minimum potential difference needed to reduce Al2O3 at 500ºC. The free energy for

decomposition reaction 2/3 Al2O3 →4/3 Al + O2 is 960KJ/mol.( 2.847V)

19. How many molecules of chlorine will be liberated by electrolysis of an aqueous solution of NaCl in 1

minute by a current of 600mA?

20. How many hours does it take to reduce 3 moles of Fe3+ to Fe2+ with a 2 ampere current?

21. A current of 100 ampere is passed through a molten solution of molten NaCl for 5 hours.

Calculate the volume of chlorine gas liberated at the anode at NTP?

Board Questions 2011

1. What type of battery is a lead storage battery? Write the anode and cathode reactions occurring in the operation of lead storage battery.

2. Calculate the potential of the half cell containing 0.10M K2Cr2O7(aq), 0.20M cr3+(aq) and 1.0 x 10-4M H+(aq). The half reaction is Cr2O7

2- + 14H+→2Cr3+ + 7H2O and the standard electrode potential is 1.33V. 3. How many moles of mercury will be produced by electrolysing1.0M Hg(NO3)2 solution with a current of 2 amp for 3

hours? (Hg(NO3)2 = 200.6g/mol)

4. A voltaic cell is set up at 25 ºC with the following half cells Al3+ (0.001M) and Ni2+(0.05M). Write an equation for the

reaction that occurs when the cell generates an electric current and determine the cell potential. Ag EºNi2+/Ni = -

0.25V; EºAl3+/Al = -1.66V

2010

1. What is meant by limiting molar conductivity? 2. Express the relationship among the cell constant, the resistance of the solution in the cell and the conductivity of the

solution. How is the conductivity of a solution related to its molar conductivity? 3. Given the standard electrode potentials, Arrange these metals in their increasing order of reducing power

.

4. Two half reactions of electrochemical cell are given below MnO4- (aq) + 8H+(aq) + 5e- → Mn2+ (aq) + 4H2O Eº = 1.51V Sn2+ (aq) → Sn4+ + e- Eº = 0.15V .Construct redox

reaction from 2 half reactions and calculate the cell potential from the standard potentials and predict if the

reaction is reactant or product favoured

2009

1. What type of battery is a lead storage battery? Write the anode and cathode reactions occurring in the operation of

a lead storage battery.

2. Two half reactions of electrochemical cell are given below MnO4- (aq) + 8H+(aq) + 5e- → Mn2+ (aq) + 4H2O Eº = 1.51V Sn2+ (aq) → Sn4+ + e- Eº = 0.15V Construct the

redox reaction from the two half reactions and calculate the cell potential from the standard potentials and

predict if the reaction is reactant or product favoured

14

3. A voltaic cell is set up at 25 ºC with the following half cells Al/ Al3+ (0.001M) and Ni2+/Ni(0.05M). Write an equation

for the reaction that occurs when the cell generates an electric current and determine the cell potential. Ag

EºNi2+/Ni = -0.25V; EºAl3+/Al = -1.66V

4. A copper silver cell is set up. The copper io concentration in it is 0.10M. The concentration of silver ion is not known.

The cell potential measured is not known. Determine the concentration of silver ion in the cell. . EºCu2+/Cu = 0.34 V;

EºAg+/Ag = 0.8V

2008

1. Depict the galvanic cell in which the reaction takes place. Further show (i) Which of the electrode is negatively

charged? (ii) The carriers of the current in the cell. (iii) Individual reaction at each electrode.

2. Write the Nernst equation and emf of the following at 298 K: Mg(s)|Mg2+(0.001M)||Cu2+(0.0001 M)|Cu(s) EºCu2+/Cu =

0.34 V;

EºMg2+/Mg = - 2.375V

3. Define conductivity and molar conductivity for the solution of an electrolyte. Discuss their variation with

concentration.

4. Three electrolytic cells A,B,C containing solutions of ZnSO4, AgNO3 and CuSO4,respectively are connected in series. A

steady current

of 1.5 amperes was passed through them until 1.45 g of silver deposited at the cathode of cell B. How long did the

current flow? What mass of copper and zinc were deposited?

Chemical kinetics

1. Define rate of reaction. 2. Why does instantaneous rate of reaction does not change when part of reacting solution is taken out? 3. When does the average rate of reaction become equal to instantaneous rate of reaction? 4. Why is instantaneous rate of reaction preferred over average rate of reaction? 5. What is rate law or rate expression ? 6. How does rate of reaction vary with reactant concentration? 7. What are the factors affecting rate of reaction? 8. Define order of reaction. 9. Define rate constant 10. How will you determine the unit of rate constant of a reaction? 11. Differentiate between elementary and complex reactions. 12. What do you mean by molecularity of a reaction? Give examples. 13. Give example of complex reaction 14. Differentiate between order and molecularity of a reaction. 15. What is meant by elementary step in a reaction? 16. What is a pseudo order reaction? Give examples. 17. Derive the integrated rate equation for zero order reaction. 18. Give examples of zero order reaction 19. Give the graphical representation of zero order reaction.

15

20. Derive the integrated rate equation for first order reaction 21. Give examples of first order reaction 22. Give the graphical representation of first order reaction 23. Derive an expression for the half life of zero order reaction 24. Define the terms threshold energy and activation energy.

What is activation energy? How is activation energy affected by

(i) use of catalyst (ii) a rise in temperature 25. Define collision frequency and effective collisions. 26. . Write a note on Arrhenius equation for rate reaction. 27. Give an example of reaction in which order and molecularity are equal. 28. In some cases, it is found that a large number of colliding molecules have more than threshold value, yet reaction

is slow, why? 29. Can a reaction have zero activation energy? 30. Predict the order of reactions for following graphs.

31. Identify the order of a reaction if the units of rate constant are i)L-1mols-1 ii) Lmol-1s-1 Numericals.

1. A first order reaction is 15% completed in 20 minutes. How long will it take to complete 60% (112.76min)

2. The rate constants of a reaction at 700K and 760 K are 0.011/M/s and 0.105/M/s respectively. Calculate the value of

Arrhenius parameters ( Ea = 166.34 KJ/mol A = 2.8 x 1010).

3. The following initial rate data was obtained for the reaction 2NO + Br2 →2NOBr

Run [NO] M [Br2] Rate M/min

1. 1.0 1.0 1.30x10-3

2. 2.0 1.0 5.2x10-3

3. 4.0 2.0 4.16 x 10-2

Determine the rate law and value of rate constant

4. The energy of activation of a reaction I 85KJ/mol. If the frequency factor is 4 x 109L/mol/s, what is the value of rate

constant at 500K? (9.06 x10-3/s)

5. For a chemical reaction the energy of activation of reaction is 85KJ/mol. If the frequency factor is 4 x 109 L/mol/s, What

isthe rate constant at 400K? (3.19 x 10-2 L/mol/s)

6. A first order reaction is 40% complete in 8 minutes. How long will it take before it is 90% complete? What is the rate

constant? (36.06 min, 0.064/min)

16

7. For a first order reaction the rate constant is 0.1/s. How much time it will take to reduce the concentration from initial

value of 0.6mol/L to 0.06mol/L? (23 sec)

8. In a first order reaction the concentration of reactants is reduced to ¼ of its original value in 50 sec. Calculate the rate

constant of the reaction. (2.77 x 10 -2/s)

9. For a reaction 2A + B → C, the rate of formation of C is 0.25 mol/l/hr. What is the rate of disappearance of A and B?(0.5

mol/L/hr 0.25 mol/L/hr.)

10. The decomposition of N2O5 according to the equation 2 N2O5 → 4NO2 + O2 is first order equation. After 30 minutes

from the start of decomposition in a closed vessel, the total pressure developed is 284.4 mm Hg and on completion, the

total 14 pressure is 584.5 mm Hg. Calculate rate constant of the reaction. (5x 10-3 /min)

11. The decomposition of a compound is found to follow first order rate law. It takes 15 minutes for 20% of original

material to react. Calculate i) the rate constant ii) the time at which 10% of the original material remains unreacted iii)

the timeit takes for next 20% of the reactants to react after 15 minutes. ( 0.0149/min; 154.6 min ; 15min)

12. Following reaction takes place in one step 2NO + O2 → 2NO2, How will the rate of above reaction change if the volume

of the reaction vessel is diminished by 1/3 of its original volume? ( 27 times)

13. For a reaction A → B, the rate of the reaction becomes 27 times when the concentration of A is increased 3 times.

What is the order of the reaction? (3)

14. Hydrolysis of ester in acid medium is a pseudo first order reaction. CH3COOC2H5 + H2O → CH3COOH +

C2H5OH. The value of rate constant k = 2 x 10-3L/mol/s. Calculate the value of k’. (0.11/s)

15. For a first order reaction calculate the ratio between the time taken to complete ½ of the reaction and the time taken

to complete 1/3 of the reaction. (1.71)

16. In a reaction N2O5 → 2NO2 + 1/2O2, the rate of disappearance of N2O5 is 6.5 x 10-3mol/L/s. Compute the rates of

formation of NO2 and O2. (1.25 x 10-2 mol/L/s ; 3.125 x 10-3 mol/L/s )

17. Find the overall order and units of rate constant i) A + 3B → 2C Rate = k*A+1/2[B]3/2

ii) 2H2 + 2NO → 2H2O + N2 Rate = [H2][NO2]

18. The rates of a reaction starting with initial concentration 2 x 10-3 M an 1 x 10-3M are equal to 2.40 x 10-4 and 0.60 x10-4

M/s. Calculate the order of reaction with respect to reactant and the rate constant (second, 60/M/s)

19. A hydrogenation reaction is carried out at 500 K. If the same reaction is carried out in the presenceof a catalyst at the

same rate, the temperature required is 400K. Calculate the Ea if the catalyst lowers the activation barrier by 20KJ/mol.

(100 KJ/mol)

20. The gas decomposition 2 N2O5 → 4NO2 + O2 follows the first order rate law. At a given temperature the rate constant

of the reaction is 7.5 x 10-3 /s. The initial pressure of N2O5 is 0.1 atm. a) Calculate the time of decomposition of N2O5 so

that the total pressure is 0.15 atm b) What will be the total pressure after 150 sec?

17

CBSE Board Questions

2011

1. What do you understand by rate law and rate constant of a reaction? Identify the order of a reaction if the units of rate constant are i)L

-1mols

-1 ii) Lmol

-1s

-1 (2)

2. The thermal decomposition of HCO2H is a first order reaction with a rate constant of 2.4 x 10-3

s-1 at a certain temperature. Calculate how long it will take for ¾ of initial quantity of HCO2H to decompose?

3. A reaction is of second order with respect to a reactant. How is the rate of a reaction affected if the concentration of the reactant is reduce d to ½. What is the unit of rate constant of such a reaction?

2010

1. a) Explain the following terms i) Rate of reaction ii) Activation energy of a reaction

b) The decomposition of phosphine PH3 proceeds according to the equation 4PH3 → P4 +6H2. It was found that thereaction

follows the following rate equation Rate = k[PH3]. The half life of PH3 is 37.9s at 120º C. i)How much time is required for ¾ of PH3

to decompose ii) What fraction of the original sample remains behind after 1 minute?

(3)

2. a) Explain the following terms i) Order of reaction ii) Molecularity of a reaction (2)

b) The rate of a reaction increase 4 times when the temperature changes from 300K to 320 K. Calculate Ea of the reaction

assuming it does not change with temperature. (3)

2009

1. A first order reaction has a rate constant of 0.0051/min. If we begin with a concentration of 0.10M concentration of the reactant,

what concentration of reactant will remain after 3 hours? 3

2. Explain the following terms i) Order of reaction ii) Activation energy of a reaction 2

3. Define the following a) Elementary step in a reaction ii) Rate of reaction 2

4. For a decomposition reaction the rate constants at 2 different temperatures are k1 = 2.15 x 10-8

L/mol/s at 650 K k2 = 2.39 x 10-7

L/mol/s at 700K. Calculate Ea for this reaction.

2008

1. The half-life for radioactive decay of 14C is 5730 years. An archaeological artifact containing wood had only 80% of the 14C found in a living

tree. Estimate the age of the sample. 3

2. Mention the factors that affect the rate of a chemical reaction.

3. A reaction is first order in A and second order in B. Write the differential rate equation.

How is the rate affected when the concentrations of both A and B are doubled? 2

4. The rate of a reaction increase 4 times when the temperature changes from 300K to 320 K. Calculate Ea of the

reaction assuming it does not change with temperature. (3)

5. Explain the following terms with an example each i) Order of reaction ii) Molecularity of a reaction (2)

6. The rate constant for a first order reaction is 60 s–1. How much time will it take to reduce the initial concentration of the reactant to its

1/16th of its initial value?

18

Accountancy:-

Do Practical Questions of the following Chapters in a Register:-

1. Accounting for Partnership Firms – Fundamentals

2. Change in Profit Sharing Ratio of Existing Partners

3. Admission of a partner

Business Studies:-

1. Prepare a file as per CBSE requirement on the Topic “Principles of Management”

2. Revise all the Chapters done in the class.

Economics:-

Do learn chapters from 1 to 8

Do numericals of Ch. 2 and Ch.3

Prepare project report on the following topics:

G.S.T.

Demonetisation

Inflation

Any topic from Macro and Indian Economic Development

Mathematics:-

MISCELLANEOUS EXERCISE

1 𝐜𝐨𝐬−𝟏(𝐜𝐨𝐬𝟏𝟑𝝅

𝟔) 2.𝐭𝐚𝐧−𝟏( 𝐭𝐚𝐧

𝟕𝝅

𝟔)3. 2𝐬𝐢𝐧−𝟏

𝟑

𝟓 =𝐭𝐚𝐧−𝟏

𝟐𝟒

𝟕

4. 𝐬𝐢𝐧−𝟏𝟖

𝟏𝟕 + 𝐬𝐢𝐧−𝟏

𝟑

𝟓 = 𝐭𝐚𝐧−𝟏

𝟕𝟕

𝟑𝟔 5. 𝐜𝐨𝐬−𝟏

𝟒

𝟓 + 𝐜𝐨𝐬−𝟏

𝟏𝟐

𝟏𝟑 = 𝐜𝐨𝐬−𝟏

𝟑𝟑

𝟔𝟓

6. 𝐜𝐨𝐬−𝟏𝟏𝟐

𝟏𝟑 + 𝐬𝐢𝐧−𝟏

𝟑

𝟓 =𝐬𝐢𝐧−𝟏

𝟓𝟔

𝟔𝟓 9.𝐭𝐚𝐧−𝟏 𝒙 =

𝟏

𝟐𝐜𝐨𝐬−𝟏

𝟏−𝒙

𝟏+𝒙 ,

x∈ 𝟎,𝟏

7. 𝐭𝐚𝐧−𝟏𝟔𝟑

𝟏𝟔 = 𝐬𝐢𝐧−𝟏

𝟓

𝟏𝟑 + 𝐜𝐨𝐬−𝟏

𝟑

𝟓 10. 𝐜𝐨𝐭−𝟏(

𝟏+𝒔𝒊𝒏𝒙+ 𝟏−𝒔𝒊𝒏𝒙

𝟏+𝒔𝒊𝒏𝒙− 𝟏−𝒔𝒊𝒏𝒙) =

𝒙

𝟐

8 𝐭𝐚𝐧−𝟏𝟏

𝟓 + 𝐭𝐚𝐧−𝟏

𝟏

𝟕 + 𝐭𝐚𝐧−𝟏

𝟏

𝟑 +𝐭𝐚𝐧−𝟏

𝟏

𝟖 =

𝝅

𝟒 11. 𝐭𝐚𝐧−𝟏(

𝟏+𝒙− 𝟏−𝒙

𝟏+𝒙+ 𝟏−𝒙)=

𝝅

𝟒−

𝟏

𝟐𝐜𝐨𝐬−𝟏 𝒙

19

12. 𝟗𝝅

𝟒-𝟗

𝟒𝐬𝐢𝐧−𝟏

𝟏

𝟑=

𝟗

𝟒𝐬𝐢𝐧−𝟏

𝟐 𝟐

𝟑

13. 2𝐭𝐚𝐧−𝟏 𝒄𝒐𝒔𝒙 = 𝐭𝐚𝐧−𝟏(𝟐𝒄𝒐𝒔𝒆𝒄𝒙)

14. 𝐭𝐚𝐧−𝟏𝟏−𝒙

𝟏+𝒙 =𝟏

𝟐𝐭𝐚𝐧−𝟏 𝒙 ,

15. sin ((𝐭𝐚𝐧−𝟏 𝒙)=?

16. 𝐬𝐢𝐧−𝟏 𝟏 − 𝒙 − 𝟐 𝐬𝐢𝐧−𝟏 𝒙 =𝝅

𝟐

17.𝐭𝐚𝐧−𝟏 𝒙

𝒚 − 𝐭𝐚𝐧−𝟏

𝒙−𝒚

𝒙+𝒚𝒊𝒔 𝒆𝒒𝒖𝒂𝒍 𝒕𝒐:

ANSWER

𝝅

𝟔 2.

𝝅

𝟔 𝟏𝟑.

𝝅

𝟒14.

𝟏

𝟑15.

𝒙

𝟏+𝒙 16. x-0, 17.

𝝅

𝟒

HOTS QUESTION

1.If 𝐭𝐚𝐧−𝟏 𝒙 +𝐭𝐚𝐧−𝟏 𝒚 + 𝐭𝐚𝐧−𝟏 𝒛 =𝝅 , prove that x+y+z=xyz

2.Prove that ; 2 𝐭𝐚𝐧−𝟏(𝐭𝐚𝐧−𝟏 𝒂−𝒃

𝒂+𝒃𝒕𝒂𝒏

𝜽

𝟐 = 𝐜𝐨𝐬−𝟏

𝒃+𝒂𝒄𝒐𝒔𝜽

𝒂+𝒃𝒄𝒐𝒔𝜽

3.solve that sin(2𝐜𝐨𝐬−𝟏(𝐜𝐨𝐭(𝟐 𝐭𝐚𝐧−𝟏 𝒙)) = 𝟎

4.solve that ;𝐬𝐢𝐧−𝟏 𝟔𝒙 + 𝐬𝐢𝐧−𝟏 𝟔 𝒙 = −𝝅

𝟐

5.prove that tan (2𝐬𝐢𝐧−𝟏𝟒

𝟓+ 𝐜𝐨𝐬−𝟏

𝟏𝟐

𝟏𝟑) =

−𝟐𝟓𝟑

𝟐𝟎𝟒

6.prove that sec2(𝐭𝐚𝐧−𝟏 𝟐) + 𝒄𝒐𝒔𝒆𝒄𝟐(𝐜𝐨𝐭−𝟏 𝟑) = 𝟏𝟓

7.if 𝐬𝐢𝐧−𝟏 𝒙 + 𝐬𝐢𝐧−𝟏 𝒚 + 𝐬𝐢𝐧−𝟏 𝒛 = 𝝅

Prove that x4+y4+z4+4x2y2z2 =2(x2y2+y2z2+z2x2)

8.Find the value of x which satisfy the equation𝐬𝐢𝐧−𝟏 𝒙 + 𝐬𝐢𝐧−𝟏 𝟏 − 𝒙 = 𝐜𝐨𝐬−𝟏 𝒙

9.Find the real solution of the equation

𝐭𝐚𝐧−𝟏 𝒙(𝟏 − 𝒙) +𝐬𝐢𝐧−𝟏 𝒙𝟐 + 𝒙 + 𝟏 =𝝅

𝟐

10.If 𝐜𝐨𝐬−𝟏𝒙

𝟐+ 𝐜𝐨𝐬−𝟏

𝒚

𝟑= 𝜶 then prove that 9x2-12xycos𝜶+4y2=36sin2𝜶

20

11.if sin(𝐜𝐨𝐭−𝟏 𝒙 + 𝟏 = 𝒄𝒐𝒔(𝐭𝐚𝐧−𝟏 𝒙) ,then find x

12.Solve the followiiing equation 𝐬𝐢𝐧−𝟏 𝟏 − 𝒙 − 𝟐𝐬𝐢𝐧−𝟏 𝒙 =𝝅

𝟐

13.if sin(𝐬𝐢𝐧−𝟏𝟏

𝟓 +𝐬𝐢𝐧−𝟏 𝒙 )=1

14if (𝐭𝐚𝐧−𝟏 𝒙)𝟐 = (𝐜𝐨𝐭−𝟏 𝒙)𝟐 =𝟓𝝅𝟐

𝟖,find x.

15.prove that cos(𝐭𝐚𝐧−𝟏(𝒔𝒊𝒏(𝐜𝐨𝐭−𝟏 𝒙)= 𝟏+𝒙𝟐

𝟐+𝒙𝟐

16.IF 𝐜𝐨𝐬−𝟏𝒙

𝜶+ 𝐜𝐨𝐬−𝟏

𝒚

𝒃= 𝜶 prove that

𝒙𝟐

𝒂𝟐−

𝟐𝒙𝒚

𝒂𝒃cos𝜶+

𝒚𝟐

𝒃𝟐=𝒔𝒊𝒏𝟐𝜶

ANSWER

3.X=±𝟏,−𝟏,−𝟏 ± 𝟐,𝟏 ± 𝟐, 4.X=±𝟏

𝟐 8.X=0, 9.X=0,-1 11.X=

−𝟏

𝟐 12.X=0,

𝟏

𝟐 13.X=

𝟏

𝟓

14.X=-1

Class –XII

Differentiation

Assignment MISCELLANEOUS EXERCISE

Differentiate w.r.t.x the function in Exercises 1 to11.

1. xx+xa+aa ,for some fixed a> 0and x> 01.(3x2-9x+5)2 2.𝒔𝒊𝒏𝟑x+ 𝒄𝒐𝒔𝟑𝒙 3.(5x)3cos2x 4.𝐬𝐢𝐧−𝟏 𝒙 𝒙

5 𝐜𝐨𝐬−𝟏

𝒙

𝟐

𝟐𝒙+𝟕 6. 𝐜𝐨𝐭−𝟏(

𝟏+𝒔𝒊𝒏𝒙+ 𝟏−𝒔𝒊𝒏𝒙

𝟏+𝒔𝒊𝒏𝒙− 𝟏−𝒔𝒊𝒏𝒙) 7.(logx)logx 8.cos(acosx+bsinx) 9.(sinx-cosx)(sinx-cosx)

11.𝒙𝒙𝟐−𝟑+(x-3)𝒙

𝟐 12.find

𝒅𝒚

𝒅𝒙,if y=12(1-cost),x=10(t-sint),

13find 𝒅𝒚

𝒅𝒙,.if y=𝐬𝐢𝐧−𝟏 𝒙+𝐬𝐢𝐧−𝟏 𝟏 − 𝒙𝟐,

14.if x 𝒙 + 𝟏 + y 𝟏 + 𝒙 =0,for -1≤ 𝒙 ≤ 𝟏,prove that 𝒅𝒚

𝒅𝒙=

−𝟏

(𝟏+𝒙)𝟐

15.if (x-a)𝟐+(y-b)𝟐=c2,for some c≥ 𝟎,prove that ((𝟏+(

𝒅𝒚

𝒅𝒙)𝟐)

𝟑𝟐

𝒚𝑰𝑰 is a constent independent of a & b

16.if cosy=xcos(a+y) with cosa ≠ 𝟏,prove that 𝒅𝒚

𝒅𝒙=

(𝒄𝒐𝒔𝟐(𝒂+𝒚)

𝒔𝒊𝒏𝒂

21

17.if x=a(cost+tsint)and y=a(sint-tcost) find 𝒅𝟐𝒚

𝒅𝒙𝟐

18.if f(x)= 𝒙 𝟑 ,show that 𝒇𝑰𝑰(𝒙) exists for all real xand find it.

19. Using mathematical induction prove that 𝒅

𝒅𝒙(𝒙𝒏)=n𝒙𝒏−𝟏for all positive integer n.

20.Using the fect that sin(A+B)=sinAcosB+cosAsinB and the differention obtain the some formula for cosines.

21. Does there exist a function which is continuous every where but not differentiable at exactly to points

?justify your answer.

22.if y=… 𝒇(𝒙) 𝒈(𝒙) 𝒉(𝒙)𝒍 𝒎 𝒏𝒂 𝒃 𝒄

prove that 𝒅𝒚

𝒅𝒙= 𝒇𝑰(𝒙) 𝒈𝑰(𝒙) 𝒉𝑰(𝒙)𝒍 𝒎 𝒏𝒂 𝒃 𝒄

23.if y=𝒆𝒂𝐜𝐨𝐬−𝟏 𝒙,-1 ≤ 𝒙 ≤ 𝟏,show that (1-x2)

𝒅𝟐𝒚

𝒅𝒙𝟐 - x

𝒅𝒚

𝒅𝒙-a2y=0

ANSWER

1.27(3x2-9x+5)8(2x-3) 2.3sinxcosx(sinx-2cos4x) 3.(5x)3cos2x(𝟑𝒄𝒐𝒔𝟐𝒙

𝒙 -6sin2xlog5x)

4.𝟑

𝟐 𝟓 .−(

𝟏

𝟒−𝒙𝟐 𝟐𝒙+𝟕+

𝐜𝐨𝐬−𝟏𝒙

𝟐

(𝟐𝒙+𝟕)𝟑𝟐

𝒙

𝟏−𝒙𝟑

6.𝟏

𝟐 7.(logx)logx(

𝟏

𝒙+𝒍𝒐𝒈(𝒍𝒐𝒈𝒙)

𝒙) 8.(asinx-bcosx)sin(acosx+bsinx)

9.(sinx-cosx)(sinx-cosx)(cosx+sinx)(1+log(sinx-cosx),sinx≥ 𝒄𝒐𝒔𝒙 10.xx(1+logx)+axa-1+axloga

11.𝒙𝒙𝟐−𝟑(

𝒙𝟐−𝟑

𝒙 +2xlogx)+(x-3)𝒙

𝟐(𝒙𝟐

𝒙−𝟑+ 𝟐𝒙𝒍𝒐𝒈(𝒙 − 𝟑) 12.

𝟔

𝟓cot

𝒕

𝟐 13.0 17.

𝒔𝒆𝒄𝟑𝒕

𝒂𝒕

Class –XII

Differentiation-2

Assignment

1. find the 𝒅𝒚

𝒅𝒙 𝒂𝒕 x=

𝝅

𝟐 if y= 𝒔𝒊𝒏𝟒𝒙𝟐 + 𝒄𝒐𝒔𝟒𝒙𝟐 . ANS.0

2. if y=2𝐭𝐚𝐧−𝟏 𝒙−𝒂

𝒃−𝒙 𝒂𝒏𝒅 𝒂 < 𝑥 < 𝑏 show that (

𝒅𝒚

𝒅𝒙)𝟐 +

𝟏

𝟗𝒙−𝒂)(𝒙−𝒃)=0

3. Differentiate the following w.r.t.x:log10x+logx10+logxx+log1010

4. Find 𝒅𝒚

𝒅𝒙, 𝒊𝒇 𝒚 =logsinxcosx ANS.

−𝒕𝒂𝒏𝒙𝒍𝒐𝒈𝒔𝒊𝒏𝒙+𝒄𝒐𝒕𝒙𝒍𝒐𝒈𝒄𝒐𝒔𝒙

(𝒍𝒐𝒈𝒔𝒊𝒏𝒙)𝟐

5. If 𝟏 − 𝒙𝟔 + 𝟏 − 𝒚𝟔=a(x3-y3),prove that𝒅𝒚

𝒅𝒙 =𝒙𝟐

𝒚𝟐 𝟏−𝒚𝟔

𝟏−𝒙𝟔 .

6. If f(x)=(𝟑+𝒙

𝟏+𝒙)𝟐+𝟑𝒙, find fI(0) ANS.-12+27log3

7. If y=log (1+cosx),prove that 𝒅𝟑𝒚

𝒅𝒙𝟑+

𝒅𝟐𝒙

𝒅𝒙𝟐.𝒅𝒚

𝒅𝒙= 𝟎.

8. If y=A𝒆−𝒌𝒕cos(pt+c),prove that 𝒅𝟐𝒚

𝒅𝒙𝟐+2k

𝒅𝒚

𝒅𝒙+ 𝒏𝟐𝒚=0,when n2=p2+k2

22

9. If f(x)= 𝒙𝟐 + 𝟏; g(x)=𝒙+𝟏

𝒙𝟐+𝟏 and h(x)=2x-3,then find fI(hI(gI(x)). ANS.

𝟐

𝟓

10. Differential the following function w.r.t.x; 𝐭𝐚𝐧−𝟏( 𝒙(𝟑−𝒙)

𝟏−𝟑𝒙) Ans.

𝟑

𝟐(𝟏+𝒙) 𝒙

11. If y=𝐬𝐢𝐧−𝟏(𝒙𝟐 𝟏 − 𝒙𝟐 + 𝒙 𝟏 − 𝒙𝟒); show that 𝒅𝒚

𝒅𝒙=

𝟐𝒙

𝟏−𝒙𝟒 +

𝟏

𝟏−𝒙𝟐 .

12. If y=log ( 𝒙 +𝟏

𝒙), prove that

𝒅𝒚

𝒅𝒙 =

𝒙−𝟏

𝟐𝒙(𝒙+𝟏).

13. If xlogy+ylogx=1,prove that 𝒅𝒚

𝒅𝒙=−𝒚(𝒚+𝒙𝒍𝒐𝒈𝒚)

𝒙(𝒙+𝒚𝒍𝒐𝒈𝒙)

14. If 𝒆𝒙 + 𝒆𝒚 = 𝒆𝒙+𝒚 ,prove that 𝒅𝒚

𝒅𝒙= -𝒆𝒚−𝒙

15. y 𝟏 − 𝒙𝟐 + 𝒙 𝟏 − 𝒚𝟐 = 𝟏,𝒑𝒓𝒐𝒗𝒆𝒕𝒉𝒂𝒕𝒅𝒚

𝒅𝒙= −

𝟏−𝒚𝟐

𝟏−𝒙𝟐.

16. If 𝟏 − 𝒙𝟐 + 𝟏 − 𝒚𝟐 =a(x-y),prove that𝒅𝒚

𝒅𝒙=

𝟏−𝒚𝟐

𝟏−𝒙𝟐.

17. If 𝐭𝐚𝐧−𝟏𝒙𝟐−𝒚𝟐

𝒙𝟐+𝒚𝟐= 𝒂,prove that

𝒅𝒚

𝒅𝒙=

𝒙(𝟏−𝒕𝒂𝒏𝒂)

𝒚(𝟏+𝒕𝒂𝒏𝒂)

18. If x 𝟏 + 𝒚 +y 𝟏 + 𝒙 =0,prove that 𝒅𝒚

𝒅𝒙 =-

𝟏

(𝟏+𝒙)𝟐

19. find𝒅𝒚

𝒅𝒙, cos(x+y)=ysinx, Ans. –

𝒚𝒄𝒐𝒔𝒙+𝒔𝒊𝒏(𝒙+𝒚)

𝒔𝒊𝒎 𝒙+𝒚 +𝒔𝒊𝒏𝒙

20. if xy=ex-y,prove that 𝒅𝒚

𝒅𝒙=

𝒍𝒐𝒈𝒙

(𝟏+𝒍𝒐𝒈𝒙)𝟐= 𝒍𝒐𝒈𝒙(𝒍𝒐𝒈𝒆𝒙)−𝟐

21. if xpyq=(x+y)p+q, prove that 𝒅𝒚

𝒅𝒙=

𝒚

𝒙

22. (cosx)𝒚 =(siny)x find 𝒅𝒚

𝒅𝒙 =𝒍𝒐𝒈𝒔𝒊𝒏𝒚+𝒚𝒕𝒂𝒏𝒙

𝒍𝒐𝒈𝒄𝒐𝒔𝒙−𝒙𝒄𝒐𝒕𝒚

23. Y=(xcosx)x+(xsinx)𝟏

𝒙 find𝒅𝒚

𝒅𝒙= (𝒙𝒄𝒐𝒔𝒙)𝒙(1xtanx+log(xcosx)+(xsinx)

𝟏

𝒙(𝟏+𝒙𝒄𝒐𝒕𝒙−𝒍𝒐𝒈(𝒙𝒔𝒊𝒏𝒙)

𝒙𝟐)

24. X=𝒆𝒄𝒐𝒔𝟐𝒕 and y=𝒆𝒔𝒊𝒏𝟐𝒕 ,prove that 𝒅𝒚

𝒅𝒙=

−𝒚𝒍𝒐𝒈𝒙

𝒙𝒍𝒐𝒈𝒚

25. If x= 𝒂𝐬𝐢𝐧−𝟏 𝒕 ,y= 𝒂𝐜𝐨𝐬

−𝟏 𝒕 ,show that 𝒅𝒚

𝒅𝒙=

−𝒚

𝒙

26. If y=tanx+secx,prove that 𝒅𝟐𝒚

𝒅𝒙𝟐=

𝒄𝒐𝒔𝒙

𝟏−𝒔𝒊𝒏𝒙)𝟐

27. If y=A𝒆𝒎𝒙 + 𝑩𝒆𝒏𝒙 prove that y2-(m+n)y1+mny=0

28. If y=𝒆𝒎𝐬𝐢𝐧−𝟏 𝒙,show that (1-x2)y2-xy1=m2y.

29. If y=(x+ 𝒙𝟐 + 𝟏)𝒎 ,show that(x2+1)y2+xy1-m2y=0

30. If x=sint,y=sinpt,prove that (1-x2)y2-xy1+p2y=0

Class –XII

Application of Derivatives

Assignment

1.Using differentials ,find the approximate value of each of the following. (i) (𝟏𝟕

𝟖𝟎)𝟏

𝟒 (ii) (33)−𝟏

𝟓

2.show that the function given by f(x)=𝒍𝒐𝒈𝒙

𝒙 has maximum at x=e.

3.The two equal sides of an isosceles triangle with fixed base b are decreasing at rate of 3cm per second ,How fast is the area decreasing when the equal isides are equal to the base?

23

4.Find the equation of the normal to curve y2=4x at the point (1,2),

5.Show that the normal at any point 𝜽 to the curve x=a cos𝜽 + a𝜽𝒔𝒊𝒏𝜽,𝒚 = 𝒂𝒔𝒊𝒏𝜽 − 𝒂𝜽𝒄𝒐𝒔𝜽 is at a constant distance from the origen.

6.Find the intervals in which the function f given by f(x)=𝟒𝒔𝒊𝒏𝒙−𝟐𝒙−𝒙𝒄𝒐𝒔𝒙

𝟐+𝒄𝒐𝒔𝒙 is (i) increasing (ii) decreasing.

7.Find the intervals in which the function by f(x)= x3+𝟏

𝒙𝟑 ,x≠ 𝟎 (𝐢) 𝐢𝐧𝐜𝐫𝐞𝐚𝐬𝐢𝐧𝐠 (𝐢𝐢) 𝐝𝐞𝐜𝐫𝐞𝐚𝐬𝐢𝐧𝐠.

8.Find the maximum area of an isosceles triangle inscribed in the ellipse 𝒙𝟐

𝒂𝟐+

𝒚𝟐

𝒃𝟐 =1 with its vertex at one end

of the major axis.

9.A tank with rectangle base and rectangular sides ,open at top is to be constructed so that its depth is 2m and volume is 8m3.if building of tank Rs.70 per sq.meters for the base and Rs. 45 per square metre for sides.What is the cost of least expensive tank.

10.The sum of the perimeter of a circle and square is k,where k is some constant.Prove that the sum of their area is least when the side of square is double the radius of the circle.

11.A window is in the form of a rectangle surmounted by a semi-circular opening .The total perimeter of the window is 10m.Find the dimensions of the window to admit maximum light through the whole opening,

12.A point on the hypotenuse of triangle is at distance a and b from the sides of the triangle ,Show that the

minimum length of the hypotenuse is (𝒂𝟐

𝟑 + 𝒃𝟐

𝟑 )𝟑

𝟐

13.Find the points at which the function f given by f(x(x-2)4 (x+1)3 has (i)local maximum, (ii) local minimum (iii) point of inflexion

14.Find the absolute maximum and minimum value of the function f given by f(x)=cos2x+sinx,x∈ 𝟎,𝝅

15.Show that the altitude of the right circular cone of maximum volume that can be inscribed in a sphere of

radius r is 𝟒𝒓

𝟑

16.Let f be a function defined on 𝒂,𝒃 such that fI(x)> 0, 𝑓𝑜𝑟 𝑎𝑙𝑙 𝑥 ∈ 𝒂,𝒃 . 𝒕𝒉𝒆𝒏 prove that f is an increasing function on (a,b).

17.Show that the height of the cylinder of maximum volume that can be inscribed in a sphere of radius R is 𝟐𝑹

𝟑

.Also find the maximum volume.

18.Show that height of the cylinder of greatest volume which can be inscribed in a right circular cone of height

h and semi vertical angle 𝜶 𝒊𝒔 one –third that of cone and the greatest volume f cylinder is 𝟒

𝟐𝟕𝝅𝒉𝟑𝒕𝒂𝒏𝟐𝜶

19.A cylindrical tank of radius 10m being filled with wheat at the rate of 314 cubic meter per hour .then the depth of the wheat is increasing at the rate of ?

20.The slope of the tangent to the curve x= t2+3t-8 ,y=2t2-2t-5 at the point (2,-1) is ?

21. the line y=mx+1 is a tangent to th curve y2=4x if the value of m is?

22 THE NORMAL AT THE POINT (1,1) ON THE CURVE 2Y+X2=3 IS?

24

23.The normal to the curve x2=4y passing (1,2) IS ?

24.The point on the curve 9y2=x3,where the normal to the curve makes equal intercept with the axies are ?

ANSWER 1.(a) 0.677 (b) 0.497 (3). b 𝟑𝒄𝒎𝟐 ( 4).x+y-3=0 ( 6).(i) 0< 𝑥 <𝝅

𝟐 and

𝟑𝝅

𝟐< 𝑥 < 2𝜋 (7).(i)x< −1

and x> 1,(ii)-1< 𝑥 < 1

(8). 𝟑 𝟑

𝟒ab (9).Rs.1000 (11).length=

𝟐𝟎

𝝅+𝟒 𝒃𝒓𝒆𝒂𝒕𝒉 =

𝟏𝟎

𝝅+𝟒 13.L.Max.atx=2,L.Min.atx=

𝟐

𝟕,point of inflection

at x=-1 (14).Absolute max.=𝟓

𝟒,Absolute min=1 (17)

𝟒𝝅𝑹𝟑

𝟑 𝟑 (19)1m3/h (20)

𝟔

𝟕 (21) 1 (22)x-y=0 (23)x+y=3

(24)(4,±𝟖

𝟑)

Class –XII

Application of Derivatives-2

Assignment

1. show that the rectangle of maximum area ,that can be inscribed in a circl e of radius r is a square of side 𝟐𝒓.

2.if the sum of the length of the hypotenuse and a side of a right angled triangle is given , show that the area of the

triangle is maximum when the angle between them is 𝝅

𝟑

3.A window has the shape of a rectangle surmounted by an equailateral triangle.if the perimeter of the window is 12

m.find the dimensions of the rectangle that will produce the largest area of the window. X=𝟏𝟐

𝟔− 𝟑𝒎, 𝒚 =

𝟏𝟖−𝟔 𝟑

𝟔− 𝟑𝒎.

4.Find the maximum area of a trapezium when the length of its three sides other than the base are 10cm.

Ans. X=5, Area 75 𝟑.

5.Show that a right circular cylinder which is open at the top and has a given surface area,will have the greatest volume

if its height is equal to the radius of its base.

6.Prove that the volume of the largest cone that can be inscribed in a sphere of radius R is 𝟖

𝟐𝟕 of the volume of sphere.

7.Show that the semi –vertical angle of the cone of the cone of maximum volume and given slant height is 𝐭𝐚𝐧−𝟏 𝟐.

8Find the points of local maximum and local minimum of the following function .also find the local maximum and local

minimum values. F(x)=X6-6X2+9X+15

Ans.L.Max.Value=68 atx=1,L.Min.Value=-316atx=5,-1647atx=-6

9.A tank with rectangular base and rectangular sides ,open at the top is to be constructed so that its depth is 2m and

volume is 8 m3.if building of tank costs.Rs.70 per sq.m. for the base and Rs.45 per .sq.m. for sides ,what is the cost of

least expensive tank? Ans.total cost =1000.

10.Show that the isosceles triangle of maximum area that can be inscribed in a given circle is an equilateral triangle.

11.Find the area of the greatest rectangle that can be inscribed in an ellipse 𝒙𝟐

𝒂𝟐+

𝒚𝟐

𝒃𝟐= 𝟏. Ans.2ab

25

12.A given rectangular area is to be fenced off in a field whose length lies along a straight river .if no fencing is needed

along the river ,show that the least length of fencing will be required when length of the field is twice its breath.

Ans. X=2y

13.The perimeter of a triangle is 8cm.One sides is 3cm. Find the other two sides such that the triangle has maximum

area.

14.A rectangle is inscribed in a semi circle of radius r with one of its sides on the diameter of the semi-circle .Find the

dimension of the rectangle so that its area is maximum ,also find this are

15.Awire of length 36 cm.is cut in to two pieces .one of the pieces is to be made into a square and other into an

equailateral triangle .Find the length of each piece so that the sum of the area of the square and the triangle is

maximum.

16.The cost of fuel for running a bus is proportional to the square of the speed generated in km/hr.it costs Rs.48 per

hour when the bus is moving at the speed of 20km/hr.,What is the most economical speed if the fixed charges are

Rs.108 for an hour ,over and above the running chares.

17.Show that the right circular conee of least curved surface and given volume has an altitude equal to 𝟐𝒕𝒊𝒎𝒆𝒔 the

radius of the base.

18.A right circular cylinder is inscribed in a cone .show that the curved surface area of the cylinder is maximum when

the diameter of the cylinder is equal to the radius of the base of the cone.

19.Show that the volume of the greatest cylinder which can be inscribed in a cone of height h and semi-vertical angle

300is 𝟒

𝟖𝟏𝝅𝒉𝟑

20.Find the altitude of a right circular cone of maximum curved surface which can be inscribed in a sphere of radius R.

21.Te sum of surface area of a sphere and a cuboid whith sides 𝒙

𝟑,𝒙 𝒂𝒏𝒅 𝟐𝒙 is constant .show that the sum of their

volume is minimum if x is equal to three time the radius of sphere.

22. A man 2m. tall walk at a uniform speed of 5 km/hr away from a lamp post 6m high.Find the rate at which the length

of his shadow increase. Ans=2.5km/hr.

23.The volume of as spherical balloon is increasing at the rate of 20cm3/sec.find the rate of change of its surface area at

the instant when its radius is 8cm. Ans=5cm2/sec.

24.Water is running out of a conical funnel at the rate of 5cm2/sec.if the radius of the base of the funnel is 10cm and

the altitude is 20cm.find the rate at which the water level is dropping when it is 5cm from the top.what do you feel

about wastage of water? Ans=−𝟒

𝟒𝟓𝝅.

25.find the equation of tangent to the curve y=cos(x+y),-2< 𝑥 ≤ 2𝜋 that are parallel to the line x+2y=0.

Ans=2x+4y+3𝝅 = 𝟎, 𝟐𝒙 + 𝟒𝒚 − 𝟒𝝅 = 𝟎.

26.Show that the curve 2x=y2 and 2xy =k cut at right angles if k2=8.

27. find the equation of the tangent and normal to the curve y=x4-6x3+13x2-10x+5 at the point x=1. ANS. 2X-Y=1=0

,X+2Y-7=0

26

28.Seprate 𝟎,𝝅

𝟐 into sub-interval in which f(x)=sin3x is increasing or decreasing strictly. Ans.S.I.F=(0.

𝝅

𝟔) ; S.D.F.(

𝝅

𝟔,𝝅

𝟐)

29. F(x)=sinx- 𝟑𝒄𝒐𝒔𝒙,𝟎 ≤ 𝒙 ≤ 𝟐𝝅,𝒇𝒊𝒏𝒅 𝒕𝒉𝒆 𝑺. 𝑰.𝑭. ;𝑺.𝑫.𝑭 𝑨𝑵𝑺.𝑺. 𝑰.𝑭. 𝟎,𝟓𝝅

𝟔 ,

𝟏𝟏𝝅

𝟔,𝟐𝝅 ,𝑺.𝑫.𝑭(

𝟓𝝅

𝟔,𝟏𝟏𝝅

𝟔)

30.FIND the local maximum or local minimum value of the function f(x)= sinx-cosy,𝟎 ≤ 𝒙 ≤ 𝟐𝝅.

31. Find the points of local maximum and local minimum of the following function .also find the local maximum and

local minimum values. F(X)=2sinx+sin2x in 𝟎,𝟐𝝅 ANS.L.MAX=𝟑 𝟑

𝟐 AT X=

𝝅

𝟔;L.Min.=

𝟏

𝟐 at x=

𝝅

𝟐.

32. Show that the semi –vertical angle of a right circular cone of given surface area and maximum volume is 𝐬𝐢𝐧−𝟏𝟏

𝟑.

Fine Art:-

1. Prepare any five illustration work on the following topics with any medium * Mountain tracking Scene *Boys playing football *School children planting saplings *Any festival * Girl is teaching alphabets to the parents *Market Scene *Scene of Railway station * Girls playing Hockey 2. Prepare any two posters with any medium

Physical Education:-

Prepare an assignment on ‘How to organise the Sports Day’ in your school.

Psychology:-

Case Profile Of An Individual Related To Any Psychological Disorder.

Revise Syllabus

History:-

PREPARE PROJECT ON FOLLOWING TOPICS:-

1.Harappan Civilisation

2.Rise Of Jainism & Buddhism

3. Mughal Empire

4. Colonial Period In India

5.Revise Syllabus

Geography:-

Prepare a project file on topic “Geographical perspective on selected issues and problems”.

27

Political Science:-

1. Prepare a presentation on Chapter No. 1 (The Cold war era) and chapter 7 (International Organisation).

2. Test of Chapter No. 1,2,3 and 4

Hindi:-

Home work for Parents

Dear Parents,

We are the caretakers of your ward/s. You might have noticed that they feel very happy to come to school.

We are providing the best infrastructure, academics, activities and sports, which are very important for the

growth and development of your ward/s. Your ward/s are really enjoying our care and attention and we do

understand that the school life is the most important period of their life. Now you are going to spend some

good time with your ward/s as natural guardian, during summer break. Therefore, a few tips as a class teacher

I wish to share with you…

Have at least two meals together with your ward/s. Tell them many people work hard to provide you a meal.

Let him understand the importance of agriculture and the hard work of people in the fields.

Let them wash their own plate after every meal. Children learn dignity of labour from such habits.

The word or Idiom, which you get with morning SMS, discuss with them.

Visit 3 neighbours. Know more about them, click pics with them and build a good rapport with them.

Allow them to help you in cooking, let children learn to make some snacks, etc.

Take them to your workplace and let them understand that you work hard to support the family.

Try to share stories with them and tell them about your childhood and family story.

As far as possible keep them away from TV and Mobile phones.

Look into the eyes of your ward/s, thank God for giving you one, which is a absolute wonder of nature.

You and we are only a temporary custodian and in a short while she/he will be soaring where we have no role

to play. We wish you good wishes for a wonderful and marvelous vacation.