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Sun December 21, 2014

Sun December 21, 2014

plzz experts answer these questions as soon as possible
1 - why is physisorption  always exothermic ??? also define physisorption .
2-why LiCl acquires pink colour when heated with li vapours ???
3-write the complete balanced chemical equations for the folling:-
  a)Oxidation of Fe2+ by Cr2O7(2-) in acidic medium 
B)oxidation of S2O3(2-) by MnO4(2-) in neutral aq medium .
4- arrange the following in the inc order of ther basic strength in water 
   {A} C6H5NH2, (C2H5)2NH, (C2H5)3N & NH3
   {b} C2H5NH2,(C2H5)2NH, (C2H5)3N &CH3NH2 in inc of basic strength in gas phase 
5- Write one of the chemicalrxn each to illustrate the folloeing :
(a) hofmann's bromanide rxn 
(b)gabriel phthalimide synthesis
6- calculate the temp at which a solution contaning 54g of gulcose ,C6H12O6, in 250g of water will freeze .{Kf for water= 1.86kg/mol &freezing point of water =273.15k}.
7-a solution containing 16g of a substance  in 200 g of diethyl ether boils at 36.86c ,whereas pure ether boils at 35.60 c .determine the molecular mass of the solute.
8- the resistance of conductivity cellcontaining 0.001M KCLsolution at 298k bis 1500W . what is the cell constant if the conductivity of 0.001M KCL  solution at 298k is 0.146 into 10 raise to power -3.
9-an electric current passed through the collodial solution.
10- what   chemiical principle is involved inchossing a reducing agent for getting the metal from its oxide ore ? consider the metal oxides ,Al2O3 & Fe2SO3 ,and justify the choice of reducing agent in each case .
11-answer the following
  1. which neutral molecule would be isoelectronic with CLO-?
  2. out of Bi(IV) AND Sb(V) which may be stronger oxidising agent and why ???
  3. what happens when sulphur is heated with conc HNO3 ???
  4. the actinoid exibit  a larger number of oxidation states than the corresponding lanthanoids .
  5. what  is the basis   of formation of the spectrochemical series .
  6. why are haloalkane more reactive towards the nucleophilic substitution rxn than haloarenes?
  7. write the structure of 1-bromo-4-sec-butyl-2-methylbenzene .
  8. what happens when D-gulcose is treated with the following  reagents -(a)HI (B)Bromine water (c)HNO3
  9. Write the name and structure of monomer of polysteyrene?
  10. mention the use of ranitidine.(DRUG)
  11. Depict the galvanic cell in which the rxn is:- Cu(S)+ 2Ag+(aq)-----------) Cu2+ (aq)+ 2Ag(s)
  12. derive the general expression for half life of first order rxn ?
  13. the decomposiion of NH3 on the planitium surface is a zero order rxn . what would be te rate of production of N2 and H2 if { k= 2.5 into 10 raise to the power -3.}
  14. list the chemical factors which determine the rate of chemical rxn 
  15. the half life for decay of radioactive C14 is 5730 years. an archological artefect containing wood had only 80% of the carbon (14)  activity  as found in aliving tree .calculate the age of the artefect .
  16. ammonia has greater affinity for protons than phosphine (PH3).
  17. the negetive value of elecron gain enthaply off fluorine is less than that of chlorine .
  18.  of noble gases, only xenon is known to  form well established chemical  compounds.
  19. state the tst to distinguish b/w the following :- (a) propanal and propanone  , (b_) phenol and benzoic acid (c)acetophenone and benzophenone  (d) ethanal and propanal
  20. write a rnx  of decarboxylation
  21. draw the structure of following (A) PCL5(g) , (B)S8(s) , (C) CIF3(g)

Sun December 21, 2014

plzz experts answer these questions as soon as possible
1 - why is physisorption  always exothermic ??? also define physisorption .
2-why LiCl acquires pink colour when heated with li vapours ???
3-write the complete balanced chemical equations for the folling:-
  a)Oxidation of Fe2+ by Cr2O7(2-) in acidic medium 
B)oxidation of S2O3(2-) by MnO4(2-) in neutral aq medium .
4- arrange the following in the inc order of ther basic strength in water 
   {A} C6H5NH2, (C2H5)2NH, (C2H5)3N & NH3
   {b} C2H5NH2,(C2H5)2NH, (C2H5)3N &CH3NH2 in inc of basic strength in gas phase 
5- Write one of the chemicalrxn each to illustrate the folloeing :
(a) hofmann's bromanide rxn 
(b)gabriel phthalimide synthesis
6- calculate the temp at which a solution contaning 54g of gulcose ,C6H12O6, in 250g of water will freeze .{Kf for water= 1.86kg/mol &freezing point of water =273.15k}.
7-a solution containing 16g of a substance  in 200 g of diethyl ether boils at 36.86c ,whereas pure ether boils at 35.60 c .determine the molecular mass of the solute.
8- the resistance of conductivity cellcontaining 0.001M KCLsolution at 298k bis 1500W . what is the cell constant if the conductivity of 0.001M KCL  solution at 298k is 0.146 into 10 raise to power -3.
9-an electric current passed through the collodial solution.
10- what   chemiical principle is involved inchossing a reducing agent for getting the metal from its oxide ore ? consider the metal oxides ,Al2O3 & Fe2SO3 ,and justify the choice of reducing agent in each case .
11-answer the following
  1. which neutral molecule would be isoelectronic with CLO-?
  2. out of Bi(IV) AND Sb(V) which may be stronger oxidising agent and why ???
  3. what happens when sulphur is heated with conc HNO3 ???
  4. the actinoid exibit  a larger number of oxidation states than the corresponding lanthanoids .
  5. what  is the basis   of formation of the spectrochemical series .
  6. why are haloalkane more reactive towards the nucleophilic substitution rxn than haloarenes?
  7. write the structure of 1-bromo-4-sec-butyl-2-methylbenzene .
  8. what happens when D-gulcose is treated with the following  reagents -(a)HI (B)Bromine water (c)HNO3
  9. Write the name and structure of monomer of polysteyrene?
  10. mention the use of ranitidine.(DRUG)
  11. Depict the galvanic cell in which the rxn is:- Cu(S)+ 2Ag+(aq)-----------) Cu2+ (aq)+ 2Ag(s)
  12. derive the general expression for half life of first order rxn ?
  13. the decomposiion of NH3 on the planitium surface is a zero order rxn . what would be te rate of production of N2 and H2 if { k= 2.5 into 10 raise to the power -3.}
  14. list the chemical factors which determine the rate of chemical rxn 
  15. the half life for decay of radioactive C14 is 5730 years. an archological artefect containing wood had only 80% of the carbon (14)  activity  as found in aliving tree .calculate the age of the artefect .
  16. ammonia has greater affinity for protons than phosphine (PH3).
  17. the negetive value of elecron gain enthaply off fluorine is less than that of chlorine .
  18.  of noble gases, only xenon is known to  form well established chemical  compounds.
  19. state the tst to distinguish b/w the following :- (a) propanal and propanone  , (b_) phenol and benzoic acid (c)acetophenone and benzophenone  (d) ethanal and propanal
  20. write a rnx  of decarboxylation
  21. draw the structure of following (A) PCL5(g) , (B)S8(s) , (C) CIF3(g)

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