CLASS 11 HOLIDAY HOME WORK 2016-17

Dear children answer the question given chapter wise in the syllabus we have done.

Topic: SOME BASIC CONCEPTS OF CHEMISTRY

1.      What is the value of one mole?

2.       Calculate the number of molecules present in 0.5 moles of CO2?

3.      1L of a gas at STP weighs 1.97g. What is molecular mass?

4.       Write empirical formula of following

CO, Na2CO3, KCl, C6H12, H2O2, H3PO4, Fe2O3, N2O4.

5.      Write an expression for molarity and molality of a solution.

6.      Calculate the weight of lime (CaO) obtained by heating 2000kg of 95% pure lime stone (CaCO3)

7.      What is the difference between precision and accuracy?

8.      What do you understand by significant figures?

9.      State law of definite proportions.

10.  Explain law of multiple proportions with an example.

11.  Define one atomic mass unit (amu).

Topic: ATOMIC STRUCTURE

12.  What is the meaning of quantization of energy?

13.  Which quantum number determines (i) energy of electron (ii) Orientation of orbitals.

14.  Write the electronic configuration of (i) Mn4+, (ii) Fe3+ (iii) Cr2+ and Zn2+ Mention the number of unpaired electrons in each case.

15.  Define photoelectric effect.

16.  How does the intensity of light effect photoelectrons?

17.  Calculate energy of 2mole of photons of radiation whose frequency is 14 5 10 . × Hz

18.  What transition in the hydrogen spectrum would have the same wavelength as the Balmer transition, n = 4 to n = 2 of He+ spectrum?

19.  Spectral lines are regarded as the finger prints of the elements. Why?

20.  States Heisenberg’s Uncertainty Principle. Give the mathematical expression of uncertainty principle.

21.  We don not see a car moving as a wave on the road why?

22.  What is the physical significance of  ψ² ?

23.  Give the range of wavelength of the visible spectrum.

24.  What is an electromagnetic radiation?

25.  Define black body radiation.

Topic: CLASSIFICATION OF ELEMENTS

26.  What is the general outer electronic configuration of f – block elements?

27.  Why do Na and K have similar properties?

28.  Why does electronegativity value increases across a period and decreases down period?

29.  Why does the ionization enthalpy gradually decreases in a group?

30.  Define valency.

31.  Why does lithium form covalent bond unlike other alkali which forms ionic bond?

32.  Predict the position of the element in the periodic table satisfying the electronic configuration (n-1) d1 ns2 for n=4,

33.  Explain why cations are smaller and anions are larger in radii than their parent atom?

34.  Na+ has higher value of ionization enthalpy than Ne, though both have same electronic configuration.

Topic: CHEMICAL BONDING

35.  Define bonding molecular orbital. Define antibonding molecular orbital.

36.  Explain diagrammatically the formation of molecular orbital by LCAO.

37.  Which one 2- 2 2 O and O , − may exhibit paramagnetism?

38.  Define hybridisation.  Give the features of hybridisation.

39.  Describe the shape of sp, sp2 and sp3 hybrid orbital?

40.  State the hybrid orbitals associated with B in BCl3 and C in C2H4

41.  In H2O, H2S, H2Se, H2Te, the bond angle decreases though all have the same bent shape. Why?

42.  What type of hybridisation takes place in (i) p in PCL5 and (ii) S in S F6?

43.  What is sigma bond? What is pi – bond?

44.  How many σ - and π - bonds are there in a molecule of CH2 = CH – CH = CH2 ?

45.  What is zero over lap?

46.  Give the main features of VSEPR Theory.

47.  CO2 is linear whereas SO2 is bend – shaped. Give reason.

48.  How is VBT different from Lewis concept?

49.  In SF4 molecule, the lp electrons occupies an equatorial position in the trigonal bipyramidal arrangement to an axial position. Give reason.

50.  Define dipole moment. Give the mathematical expression of dipole moment.

51.  Why NH3 has high dipole moment than NF3 though both are pyramidal?

52.  Draw the resonating structure of NO3 –

53.  On which factor does dipole moment depend in case of polyatomic molecules.

54.  Which one of the following has the highest bond order? N2, N2 + or N2 - .

55.  Give reason why H2 + ions are more stable than H2 - though they have the same bond order.

56.  Write electron dot structure (Lewis structure) of Na, Ca, B, Br, Xe, As, Ge, N3-.

Topic: STATES OF MATTER

57.  Write Van der waal’s equation for n moles of a gas. Out of NH3 and N2, which will have (i) larger value of ‘a’ and (ii) larger value of ‘b’?

58.  Under what conditions do real gases tend to show ideal gas behaivour?

59.  Calculate the pressure exerted by one mole of CO2 at 273 k if the Van der waal’s constant a = 3.592 dm6 at m mol-1. Assume that the volume occupied by CO2 molecules is negligible.

60.  What is the value of compressibility factor Z, of a gas when (i) pressure is low, (ii) pressure is high, (iii) at intermediate pressure.

61.  What is surface tension? What is its S.I unit? How does surface tension change when temperature is raised?

62.  Some tiny light hollow spheres are placed in a flask. What would happen to these spheres, if temperature is raised?

63.  At 250C and 760 mm of Hg pressure a gas occupies 600ml volume. What will be its pressure at a height where temperature is 100C and volume of the gas is 640mL.

64.  Calculate the volume occupied by 5.0 g of acetylene gas at 500C and 740mm pressure.

65.  Molecule A is twice as heavy as the molecule B. which of these has higher kinetic energy at any temperature?

66.  Why helium and hydrogen gases not liquefied at room temperature by applying very high pressure?

67.  At what temperature will the volume of a gas at 00 c double itself, pressure remaining constant?

68.  50 cm3 of hydrogen gas enclosed in a vessel maintained under a pressure of 1400 Torr, is allowed to expand to 125 cm3 under constant temperature conditions. What would be its pressure?

69.  Ice has lower density than water. Give reason. Water has maximum density at 40C. Give reason.

70.  What type of bond exists between H O2 ,HF, NH3, C2H5 OH molecule.?

Topic: THERMODYNAMICS

71.  Define spontaneous process. Define non-spontaneres process.

72.  Two ideal gases under same pressure and temperature are allowed to mix in an isolated system – what will be sign of entropy change?

73.  The  ∆  H g and∆ S for   2Ag2 O(s) →  4Ag(s) +O2  ( g) are given + 61.17kJ mol-1 and + 132 Jk-1mol-1 respectively. Above what temperature will the reaction be spontaneous?

74.  The standard heat of formation of Fe2O3 (s) is 824.2kJ mol-1 Calculate heat change for the reaction.

4Fe(s) + 302 (g) →2Fe2O3(s)

75.  Calculate the heat of combustion of ethylene (gas) to from CO2 (gas) and H2O (gas) at 298k and 1 atmospheric pressure. The heats of formation of CO2, H2O and C2H4 are – 393.7, - 241.8, + 52.3 kJ per mole respectively.

76.  Define Heat capacity ?Define specific heat? Give the mathematical expression of heat capacity.

77.  It has been found that 221.4J is needed to heat 30g of ethanol from 150C to 180C. calculate (a) specific heat capacity, and (b) molar heat capacity of ethanol.

78.  Define enthalpy. Give the mathematical expression of enthalpy.

79.  Why is the difference between ∆H and ∆U not significant for solids or liquids?

80.  Give the expression for (i) isothermal irreversible change, and (ii) isothermal reversible change.

81.  What is an extensive and intensive property?

82.  State the first law of thermodynamics.