Office 56/2 Hazra Road, 3 rd Floor Kolkata – 700 019, West Bengal, India Ph: +91 33 2476 7504 Fax: +91 33 2474 6499 Campus New Korolah, NH – 6, Alampur, Howrah – 711 302 Ph: + 91 2269 0097 / 98 www.aisedu.org Date: 20/05/2020 Ref: AIS/2020-21/0008 Holiday Homework for Class XII SC Subject : English From the following choose any two of the errands allotted: 1. Watch any two of the following movies and draw an analytical inception and elaboration upon the two in two different write ups. a. Interstellar(2014) b. The Death of Socrates(2010) c. Pursuit of Happiness(2006) d. August Rush(2007) 2. Interview your parent(s)/grand parent(s), by spending good hours with them thereby quote their wise words that their experiences have revealed. Also write a short biography of the person interviewed in 500 words. Save better memories through this holiday homework. Subject: Physics Project File Format 1. Cover Page : CBSE PRACTICAL PHYSICS Name: Sub Code: 042 Registration No: Board Roll No: SCHOOL: AIS School Code: Session: 2. Certificate: 3. Declaration: 4. Acknowledgement:
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Holiday Homework for Class XII SC - aisedu.orgaisedu.org/holiday-homework/holiday-homework-of-class-xii-science.… · Subject: Physics Class XII will do their Investigatory project
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Office 56/2 Hazra Road, 3rd Floor Kolkata – 700 019, West Bengal, India
Class XII will do their Investigatory project (final project for CBSE) as holiday homework. The projects are divided into
three categories and the projects topics are as follows.
Category 1(Experimental)
a. To find refractive index of different liquid (water, oil) using plane mirror and equiconvex lens.
b. To convert Galvanometer to Voltmeter and Ammeter using high resistor and shunt.
Category 2(Model Based)
a. To design an appropriate logic gate combination for a given truth table
b. To design an LC oscillator that produces AC from DC source.
c.
Category 3(Theoretical)
a. To study the working of an AC generator
Any ONE of the above five projects will be done by student.
Subject : Chemistry
Board level questions
MCQ’s Level I type
MCQ’s Level II type
Board Level questions:
Derive activation energy by Arrhenius equation.
What is the effect of catalyst on rate of a reaction?
Zero order reaction means that the rate of a reaction is independent of concentrations of reactants. 1. Write an example of a zero order reaction. 2. Write the integral rate expression for the zero order reaction.
Write down the unit of rate constant for first order and second order reaction.
What are the differences between order and Molecularity?
For a first order reaction, half life period is 100 sec. How long will it take for the reaction to complete 75%?
For a first order reaction, show that time required for 99% completion is twice the time required for the completion of 90% of reaction.
Derive the integrated rate equation for first order reaction.
Calculate the average rate of reaction between the time interval 30 to 60 sec. (given, log 2 = 0.3010 and log 4 = 0.6021)
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The rate of a reaction increases in the presence of a catalyst. Explain the statement by plotting a curve between reaction coordinate and energy.
For a reaction, the initial concentrations of a reactant are 0.4M and rate constant is 2.5 x 10-4 s-
1.Calculate the half life period of the reaction.
The decomposition of sulphuryl chloride to SO2 and Cl2 is a first order reaction whose half life is 30 mins. What % of the reactant will be decomposed in 2 hours?
The activation energy of a first order reaction at 300 K is 60 kJ/mol. In the presence of a catalyst, the activation energy gets lowered to 50 kJ/mol at 300 K. How many times the reaction rate changes in the presence of a catalyst at the same temperature?
A first order reaction takes 40 mins for 20% completion. Calculate its half life period.
A first order reaction is 20% complete in 10 mins. Calculate the time taken for the reaction to go to 75% complete.
Define: Half life time and order of a reaction.
The thermal decomposition of a compound is of first order. If 50% of the compound is decomposed in 120 mins, how long will it take for 90% of the compound to decompose?
Give an example of pseudo first order reaction.
Define temperature coefficient of a reaction.
MCQ’s Level I
1. Rate of formation of SO3 in the following reaction: 2SO2 + O2 2SO3 is 100gm/min. Hence, rate of disappearance of O2 is a) 5. Gm/min b) 100 gm/min c) 200 gm/min d) 20gm/min
2. For xA + yB zC; -d[a]/dt = -d[B]/dt = 1.5 d[C]/dt, then x, y and z are a) 1, 1, 1 b) 3, 2, 3 c) 3, 3, 2 d) 2, 2, 3
3. Reaction rates are determined by all of the following factors except 1. The number of collisions between molecules 2. The force of collisions between molecules 3. The orientation of collisions between molecules 4. The spontaneity of the reaction
4. For the above complex, ratio of rate constants of the forward and backward reaction is - 2 x 107 L2mol-2 - 2 x 109 L2mol-2
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5. Which of the following statement is correct? a) The rate of a reaction decreases with passage of time as the concentration of reactants decreases b) The rate of a reaction is same at any time during the reaction c) The rate of a reaction independent of temperature change d) The rate of a reaction decrease with increase in concentration of reactant(s)
6. In the following graphical representation for the reaction A B, there are two types of regions
a) I and II both represent kinetic region at different time interval b) I and II both represent equilibrium region at different time interval c) I represents kinetic while II represents equilibrium region d) I represents equilibrium while II represents kinetic region
7. Which of the following statements in not correct about order of a reaction?
a) The order of a reaction can be fractional number b) Order of a reaction is experimentally determined quantity c) The order of a reaction is always equal to the sum of the stoichiometric coefficients of reactants in the
balanced chemical equation for the reaction d) The order of a reaction is the sum of the powers of molar concentration of the reactants in the rate law
expression
8. For a reaction: 2A + 3B product; A is in excess and on changing the concentration of B from 0.1M to 0.4M, rate becomes doubled. Thus, rate law is a) dx/dt = k[A]2[B]3 b) dx/dt = k[A][B] c) dx/dt = k[A]0[B]2 d) dx/dt = k[B]1/2
9. Rate constant of the Zeroth order can be expressed as a) min-1 atm b) mol/s c) h-1L-1mol d) All of these
10. For Zeroth order reaction a) Activation energy is zero
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b) Heat of reaction is zero c) Rate of disappearance is zero d) Rate of disappearance of reactant is independent of concentration
11. A reaction of first order completed 90% in 90 min, hence it is completed 50% in approximately a) 50 min b) 54 min c) 27 min d) 62 min
12. For the first order reaction Tav, T50 and T75 in the increasing order a) T50< Tav< T75 b) T50< T75< Tav c) Tav< T50< T75 d) Tav = T50< T75
13. Half lives of first order and Zeroth order reactions are same. Ratio of rates at the start of reaction is 1. 0.693 2. 1/0.693 3. 2 x 0.693 4. 2/0.693
14. Half lives of second and third order reactions are equal. Ratio of rates of second and third order reactions at the start of the reaction is a) 2/3 b) 3/2 c) 0.693 d) 3
15. MZA(g) M-8
Z-4B(g) + α-particles. The radioactive disintegration follows first order kinetics. Starting with 1 mol of A in a 1 lit closed flask at 27oC, pressure set up after two half lives is approximately a) 25 atm b) 12 atm c) 37 atm d) 40 atm
16. For a second order reaction, 2A product, a st.line is obtained, if we plot 1) concentration vs. time 2) log(conc) vs. time 3) log(conc) vs. time-1 4) (conc)-1 vs. time
17. Time of 75% reaction is thrice of time of 50% reaction. Hence, order is a) 0
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18. Milk turns sour at 400C, three times as faster as 0oC. hence, Ea in cal of turning of milk sour is a) + 4694 b) -4694 c) 0.001012 d) None of the above
19. The role of catalyst is to change a) Gibbs free energy of reaction b) Enthalpy of reaction c) Activation energy of reaction d) Equilibrium constant
20. In the presence of a catalyst, the heat evolved or absorbed during the reaction a) Increases b) Decreases c) Remains unchanged d) May increase or decrease
MCQ’s Level II
21. The value of rate constant of a pseudo first order reaction a) Depends on the concentration of the reactants present in small amount b) Depends on the concentration of the reactants present in excess amount c) Is independent of the concentration of the reactants d) Depends only on temperature
22. Consider the graph given in figure. Which of the following options does not show instantaneous rate of reaction at 40 sec?
Office 56/2 Hazra Road, 3rd Floor Kolkata – 700 019, West Bengal, India
a) V5 – V2/20 b) V4 – V2/20 c) V3 – V2/10 d) V3 – V1 /20
23. Select the incorrect statement. a) Larger the value of activation energy, smaller the value of rate constant b) Larger the value of activation energy, greater is the effect on the value of k for a given temperature change c) At lower temperature, increase in temperature causes more change in the value of k than at higher
temperature d) k is affected by change in concentration
24. Half life period of the first order reaction is 100 days. After 144.3 days, concentration of the reactant reduced to…….of the original value a) 1/e b) 1/e2 c) 10% d) 20%
25. Number of natural life time (T) required for a first order reaction to achieve 99.9% level of completion is a) 2.3 b) 6.9 c) 9.2 d) 0.105
26. For the second order reaction, 2A Product; the initial concentration of A is 0.1M and rate constant is 2 x 10-3 dm3 mol-1 s-1. The half life period of the reaction is a) 5 sec b) 50 sec c) 500 sec d) 5000 sec
27. The activation energy of a reaction is zero. At 280 K rate constant is 1.6 x 10-6 s-1. The rate constant at 300K is a) Zero b) 3.2 x 10-6 s-1 c) 1.6 x 10-5 s- d) 1.6 x 10-6 s-1
28. Rate constant of a reaction is dependent on temperature k = A.e-Ea/RT. K has the least value at High T and high Ea High T and small Ea Low T and low Ea Low T and high Ea
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29. What function of [x], plotted against time, will give a straight line for a second order reaction? a) [x] b) [x]2 c) log [x] d) 1/[x]
30. Two reactions with different activation energies have the same rate at room temperature. What statement correctly describes the rates of these two reactions at the same higher temperature? a) The reaction with the greater activation energy will be faster b) The reaction with the small activation energy will be faster c) The reactions will have the same rate d) Temperature range is also required
31. The rate constant for the reaction, 2N2O5 4NO2 + O2 is 3 x 10-5 s-1. If the rate is 2.40 x 10-5 Ms-1, then the concentration of the N2O5(in mol/lit) is a) 1.4 b) 1.2 c) 0.04 d) 0.8
32. In a first order reaction, A Product, the ratio of a/(a-x) was found to be 8 after 60 mins. If the concentration is 0.1M then the rate of reaction is a) 2.226 x 10-3 mol L-1 min-1 b) 3.466 x 10-3 mol L-1 min-1 c) 4.455 x 10-3 mol L-1 min-1 d) 5.532 x 10-3 mol L-1 min-1
33. For n-th order reaction, Ct = CO – kt (where Co is initial concentration, Ct is the final concentration after time t). This shows that n is a) 0 b) 1 c) 2 d) 3
34. The rate constant for the reaction in gaseous phase O + O3 2O2 is 8.0 x 10-15 cm3 molecule-1 s-1 at 298 K. Corresponding value in dm3mol-1s-1 is 1. 4.8 x 106 dm3 mol-1 s-1 2. 1.33 x 10-6 dm3 mol-1 s-1 3. 4.8 x 108 dm3 mol-1 s-1 4. 1.33 x 106 dm3 mol-1 s-1
35. Time constant, τ, is required for the concentration of a reactant to fall to 1/e of its initial value, then a) kτ = 2.303 b) kτ = (2.303)-1
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36. Activation energy of a chemical reaction is determined by a) Determining the rate constant at standard temperature b) Determining the rate constant at two temperatures c) Determining the probability of collision d) Using catalyst
37. Order of a reaction is determined by a) Molecularity b) Pressure c) Temperature d) Mechanism of reaction as well as relative concentration of reactants
38. Which is correct about zero order reaction? C. Rate of reaction depends on decay constant D. Rate of reaction is independent of concentration E. Unit of rate constant is concentration-1 F. Unit of rate constant is concentration-1 time-1
39. By increasing in temperature by 10K, the rate of reaction becomes double. How many times the rate of reaction will be if the temperature is increased from 303 K to 353 k? a) 4 b) 8 c) 16 d) 32
40. Time required for 100% completion of a zero order reaction is 1. ak 2. a/2k 3. a/k 4. 2k/a
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