CBSE Guess > Papers > Important Questions > Class XII > 2007 > Chemistry > Practice Paper 2

Practice Paper 2

1. Arrange the following molecular specie in increasing order of stability?
   N2, N2+, N2- , N2’2-
2. Why dues frankel defeat not change the density of structure?
3. Why a dry cell becomes dead after a long time ever if it has not been used?
4. Define activacation energy of ?
5. Why delta are farmed where riness and sea meet?
6. Arrenge the following in the decreasing order of their ionic character?
   M-f , M-Cl, M-Br,M-I where M represents a metal.
7. Write IUPAC name of [Co(nn³)³ ONU] Cl² and also coordination no. of central metal atom?
8. Name of the products obtained when simple lipids are hydrolysed?
9. Name o a substance which can be used 120th an antiseptic as well as a disinfectiant
10. Why PCL5 is possible whereas NCl5 is not .
11. The C.E. of an electron is 5*10’5 W (electron Volt) calculate the maxlength of the associated with the electron.The mass of the clectron may be taken as 10 kg.
12. Explain the following observation.
    (i) Co2 and So2 are not isostructural ?
    (ii) O2 is paramagnetic but O2 is not?
13. Lead (II)sulphide crystal has wall structure what is the distance between Pb2+and S2- in pbs if its density is 12.7 & Cm-3.?
    (At.mass of Pb=257)
14. Addition of 0.643 of a compound to 50 ml of benzene (density: 0.87a /ml) the freezing point from 5.51 C to 5.03 C of Kf far benzene is 5.12,calculate the
    molicular weight of the compounds?
15. Differenciate between possitive deviation & negative deviation from ideal behaviour?
16. (a). An andothesmic reaction A----------B proceds to .Predict the sign of 4s.
    (b) what will be the sign of as as far the reaction N2(g)+O2(g)--------2no(g) give the reason in support of your answer?
17. For the Reaction at 298k
    N2(g)+3N2(g) --> 2Nn3(g) eahalpy& entropy changes are –92.4kj and –198.2 jk-1 respectively.calculate the equilibrium constant of the reaction.(R=8.314)
18. The standard electrode potential are given as e0 cu2f/cu= calculate the cell potential (E) for the cell containing 0.100 g +and 4.
19. (a) What happens when a fresly precipitated fe(on)2 is shaken with a little amount of of fecl3 ?
    (b) what is the role of adsorftion in heterogenous catalytic neaction?
20. Explain the following
    (A) Diborane
    (B) Phasphoric acid
21. Give proper reason
    (I) [Ni(CO)4] has tetrahedral geometry where as [Ni(CN)4]2- has square planner
    geometry. ?
    (II) [Fe(CN)6]3- is weakly paramagnetic while [Fe(CN)6]4- is dimagnetic?
22. Discuss the different confirmation of Ethane . How will you account for the
    differance in their relative stability?
23. How will you account for the following --
    (a) Methyl phenyl ether reacts with HI to give Phenol and Methyl iodide and not Iodobenzene and Methyl alcohal
    (b) The order of reactivity of Halogen acid towards cleavage of ether is :
    HI > HBr > HCl
24. How will you synthesize Teflon and Nylon –66? Identify the type of polymerization on the basis of chain growth and step formation.
25. How does the fructose differ from glucose? Draw their close chain structure.
26. What is Peptide linkage? Give the difference between polypeptide and protein?
27. How are the azo dyes prepared/ Why is the colour imparted by azo dyes to fabrics not fast?
28. When 0.532gm of benzene (C6 H6 ) boiling point 353k is burnt with excess
    Of oxygen in a constant volume system 22.3kg of heat is given out. Calculate
    For the combustion process [R = 8 .31Kj-1 mol-1]
29. the reaction
30. SO2 CL2 --------SO2 + CL2 is a first reaction with K1 = 2.2x10to the power –5Sec-1 at 575K.What percentase of SO2CL2with get decoposed in90 minutes when the reation is carried out at 575K
31. Explain the extraction of aluminium from red bouxite with equation
32. What is lanthanide contraction. Describe its consequesnces for determination of basic strength of lanthanides.
33. Explain the following name reaction:
    [I] Wolf Kishner Reduction
    [II] Hoffman Bromamide Reaction
    [III] Rimer Tiemann reaction
34. Give an account of extraction and purification of Mercury .Describe reaction which occour when an aqueous solution of Mercury II Chloride is located with –
    (i) In aqueous solution of pottassium iodide .
    (ii) An aqueous solution of tin (ii) Chloride . (iii) copper
    (iii) An aqueous solution of sodium hydroxide what peculiar does mercury have
35. (a) Describe briefly the product obtained when nitrobenzene is reduced under different condition. .
    (b) Explain why does nitrobenzene undergo electrophitic substitution reaction at the M-Position. Write the products obtained when nitrobenzene react with –
    (I) Fuming HNO3 +Conc H2SO4 at 363K .
    (II) Cl2 in presence of Fe , also explain why nitrobenzene does not undergo Friedel craft reaction.

1. Atomic Structure and Chemical Bonding
2. Solid State
3. Solutions
4. Thermodynamics
5. Electrochemistry
6. Chemical Kinetics
7. P Block Elements
8. D and F Block Elements
9. Nuclear Chemistry
10. Stereo Chemistry
11. Organic Functional Group I
12. Organic Functional Group II and III
13. Surface Chemistry
14. Chemistry In Every Day Life
15. Polymers
16. Practice Paper No.1
17. Practice Paper No.2
18. Practice Paper No.3
19. Practice Paper No.4