set 4 2017 model chemistry paper CBSE
CLASS - XII
CHEMISTRY MODEL PAPER – (043)—2017
SET-4 Time : Three hour Max. Marks : 70 General Instructions :-
1. All questions are compulsory.
2. Question No. 1-5 are very short answer questions and carry 1 mark each.
3. Question No. 6-10 is short answer questions and carries 2 marks each.
4. Question No. 11-22 is also short answer questions and carries 3 marks each.
5. Question No. 23 is value added questions and carry 4 marks.
6. Question No. 24-26 carry 5 marks
7. Use log tables if necessary, use of calculators is not allowed.
Q1.Give the monomeric structure of teflon.? 1
Q2. What are flux.How they are selected for a specific ores.? 1
Q 3. What do you mean by lanthanoid contraction. 1
Q4. Write IUPAC name of the following compound C6H5CH(OH)-COOC2H5 1
Q5. Mension one property which is caused due to the presence of F-center.?.? 1
Q6. Calculate the percentage composition in term of mass of a solution obtained by mixing 00 gm of a 25% and 400 of 40% solution by mass.? 2
Q7. (i)Write chemical reaction only which occour in blast furnance below 1200k temp.?. 2
(ii) Define how zone refining is goof for isolation of semiconductor
. Q8.Drow the structure of H3PO4 and HclO4. 2
Q9. Urea (molar mass = 60 g mol¯ 1) is present in a solution having osmotic pressure of 4.12atm. Calculate the weight of urea present in it if the room temperature is 270 c.If same weight of glucose has been taken in place of urea then find out osmotic pressure. 2
Q10. Write unit of rate constant id order is 5/2.?.
Q11.(i)Define Hardy schulze rule.? . (ii)Define faraday first law of electrolysis.. 3
Q12. (i)What are nacotic drugs.why we should not use them.? (ii)Give chemical equation when glucose react with red phosphorous and HI.. (iii)Why humane beings are unabl to digest cellulose.?.? 3
Q13. (i) What is Glycosidic linkage.give example.? (ii) What is PHBV.give their uses.. 3
Q14. (i)Describe the mechanism for the formation of 3-hydroxy butanal from ethanal.?.
(ii)Cyclohexyly chloride is more polar then chloro benzene.explain.?? 3
Q15. Write short notes on the following name reaction : 3
(i) Clemensen reaction
(ii)Rosenmund reaction
(iii)Hell volhard zelneskii reaction.
Q16. (a)Give chemical tests to distinguish between compounds in each of the following pairs:
(i) Propyl alcohol and Ethyl alcohol
(ii) Butane-2-ol and Butanaol
(b)Direct nitration of Aniline is not safe ? 3
Q17.Arrange the following compounds in
(i) HCHO,CH3CHO.CH3COCH3,CH3COCH2CH3 (Nucleophilic addition reaction)
(ii) 2-chlorobenzoic acid.2-methy benzoic acid.benzoic acid
(iii) CH3CH2CHO,.CH3COCH3,CH3CH3COCH2CH3 (Reaction toward grignard reagent) 3
OR
Account for the following:
(a) Aniline cant be prepared by Garbriel pthalamide reaction
(b) Phenol show acidic character.?
Q 18.(i) What role of semipermeable membrane play in plasmolysis..?
(ii) Write the name of defeciency desease cause by vitamins E.
(iii)Define what is adsoption isotherm.?. 3
Q19.(i) A Nacl compound has density of 6.125 g cm-3. If the edge length of its cubic unit cell is 400 pm,. Calculate the molecular mass of Nacl.?
(ii) Define what is n-type and p- type semiconductor.give example.?.
Q20. Write names of monomer/s of the following polymers and give important uses.. (b) Bakelite (c) Nylon-6 3
Q21. (a) Give the IUPAC name of :
K4[Co(cl)3 (H20)3]
(b)Drow the splitting diagrame for TETRHEDRAL complex and define what is CFSE.How its magnitude change with strngth with ligands.?. 3
Q22. Explain the following observations:
(a) What is role of NaCN in froath flotation process.?
(b) Difference beetwen lyophilic and liophobic substances.
(c) From the CO and C ,which is best reduction agent for Iron in blast furnance temperature? 3
Q23. People are advised to limit the use of fossil fuels resulting in Green House Effect leading to a rise in the temperature of earth. Hydrogen provides an ideal alternative and its combustion in fuel cells. 4
(i) White electrode reaction in H2 -O2 fuel cell.
(ii) How is green house effect reduced by the use of fuel cells? (iii) Write the values associated with preference of using fuel cells to fossil fuel. 3
Q 24. (i)There are two-NH2groupin semicarbazide. However only one is involved in formation of semicarbazones. Why?
(ii)Why are aldehydesare more reactive than ketones when undergo nucleophillic addition reaction? (iii)During preparation of esters from a carboxylic acid and an alcohol in the presence of acid catalyst water or ester formed should be removed as soon as it is formed (iv)Why does methanal not give aldol condensation while ethanol gives?
(v)Why is the boiling point ofan acid anhydride higher than the acid from which it is derived 5
OR
(a) An organic compound ‘A’ with molecular formula C8 H8 O2 is reduced to 2- ethyl phenol on treatment with LiALH 4. ‘A’ forms a oxime with hydroxylamine and gives positive lodoform test and not a Tollen’s test. Identify the compound A and deduce its structure.
(b) Write the chemical equations for the following conversions:
(i) Ethyl chloride into propanoic acid
(ii) Benzyl alcohol into Benzoic acid
(iii) Acetone to tert-Butyle alcohol
Q25. (a) How will you bring about the following conversions
(i) benzene to 3-bromonitrobenzene
(ii) ethanol to but-1-yne
(iii) 1-bromopropane to 2-bromopropane
(b)Give a chemical test to distinguish between the following pairs of compounds:
(i) chlorobenzene and cyclohexylchloride.
(ii) vinyl chloride and ethyl chloride.
OR
(a) Give reasons for the following :
(i) The bond length of C–Cl bond is larger in haloalkanes than that in haloarenes.
(ii) Although alkyl halides are polar in nature but are not soluble in water
(b) Complete thye following equation
(a) Cr2 O7-- + H + + C2H5OH-----------
(b) XeF 4 + O2 F2 ----------
(c) 2H3 PO3 ----------^------ 5
Q 26. Give reasons for the following:
(a) ClF3 is known but Fcl3 does not known. ?
(b) Carbon show more catenation then phosphorous.?
(c) ICl is more reactive than I2 ?
(d)Drow the structure of N 205.
(e)Only Xe from inert gases make compound with O and F atom. While other gases does not. 5
OR
(a)2Mn4 – + 10 I – + 16 H– --------→
(b)2Mn4 – + H2O + I– --------- →
(c )Write complete chemical equations for
(i)Compare the oxidation of Fe2+ by Cr2O7 2– in acidic medium .
(ii) oxidation of Mn2+ by MnO4 – in neutral or faintly alkaline medium.( give support equation) (d)Cr2+ or Fe2+ (which one is stronger reducing agent)
SET-4 Time : Three hour Max. Marks : 70 General Instructions :-
1. All questions are compulsory.
2. Question No. 1-5 are very short answer questions and carry 1 mark each.
3. Question No. 6-10 is short answer questions and carries 2 marks each.
4. Question No. 11-22 is also short answer questions and carries 3 marks each.
5. Question No. 23 is value added questions and carry 4 marks.
6. Question No. 24-26 carry 5 marks
7. Use log tables if necessary, use of calculators is not allowed.
Q1.Give the monomeric structure of teflon.? 1
Q2. What are flux.How they are selected for a specific ores.? 1
Q 3. What do you mean by lanthanoid contraction. 1
Q4. Write IUPAC name of the following compound C6H5CH(OH)-COOC2H5 1
Q5. Mension one property which is caused due to the presence of F-center.?.? 1
Q6. Calculate the percentage composition in term of mass of a solution obtained by mixing 00 gm of a 25% and 400 of 40% solution by mass.? 2
Q7. (i)Write chemical reaction only which occour in blast furnance below 1200k temp.?. 2
(ii) Define how zone refining is goof for isolation of semiconductor
. Q8.Drow the structure of H3PO4 and HclO4. 2
Q9. Urea (molar mass = 60 g mol¯ 1) is present in a solution having osmotic pressure of 4.12atm. Calculate the weight of urea present in it if the room temperature is 270 c.If same weight of glucose has been taken in place of urea then find out osmotic pressure. 2
Q10. Write unit of rate constant id order is 5/2.?.
Q11.(i)Define Hardy schulze rule.? . (ii)Define faraday first law of electrolysis.. 3
Q12. (i)What are nacotic drugs.why we should not use them.? (ii)Give chemical equation when glucose react with red phosphorous and HI.. (iii)Why humane beings are unabl to digest cellulose.?.? 3
Q13. (i) What is Glycosidic linkage.give example.? (ii) What is PHBV.give their uses.. 3
Q14. (i)Describe the mechanism for the formation of 3-hydroxy butanal from ethanal.?.
(ii)Cyclohexyly chloride is more polar then chloro benzene.explain.?? 3
Q15. Write short notes on the following name reaction : 3
(i) Clemensen reaction
(ii)Rosenmund reaction
(iii)Hell volhard zelneskii reaction.
Q16. (a)Give chemical tests to distinguish between compounds in each of the following pairs:
(i) Propyl alcohol and Ethyl alcohol
(ii) Butane-2-ol and Butanaol
(b)Direct nitration of Aniline is not safe ? 3
Q17.Arrange the following compounds in
(i) HCHO,CH3CHO.CH3COCH3,CH3COCH2CH3 (Nucleophilic addition reaction)
(ii) 2-chlorobenzoic acid.2-methy benzoic acid.benzoic acid
(iii) CH3CH2CHO,.CH3COCH3,CH3CH3COCH2CH3 (Reaction toward grignard reagent) 3
OR
Account for the following:
(a) Aniline cant be prepared by Garbriel pthalamide reaction
(b) Phenol show acidic character.?
Q 18.(i) What role of semipermeable membrane play in plasmolysis..?
(ii) Write the name of defeciency desease cause by vitamins E.
(iii)Define what is adsoption isotherm.?. 3
Q19.(i) A Nacl compound has density of 6.125 g cm-3. If the edge length of its cubic unit cell is 400 pm,. Calculate the molecular mass of Nacl.?
(ii) Define what is n-type and p- type semiconductor.give example.?.
Q20. Write names of monomer/s of the following polymers and give important uses.. (b) Bakelite (c) Nylon-6 3
Q21. (a) Give the IUPAC name of :
K4[Co(cl)3 (H20)3]
(b)Drow the splitting diagrame for TETRHEDRAL complex and define what is CFSE.How its magnitude change with strngth with ligands.?. 3
Q22. Explain the following observations:
(a) What is role of NaCN in froath flotation process.?
(b) Difference beetwen lyophilic and liophobic substances.
(c) From the CO and C ,which is best reduction agent for Iron in blast furnance temperature? 3
Q23. People are advised to limit the use of fossil fuels resulting in Green House Effect leading to a rise in the temperature of earth. Hydrogen provides an ideal alternative and its combustion in fuel cells. 4
(i) White electrode reaction in H2 -O2 fuel cell.
(ii) How is green house effect reduced by the use of fuel cells? (iii) Write the values associated with preference of using fuel cells to fossil fuel. 3
Q 24. (i)There are two-NH2groupin semicarbazide. However only one is involved in formation of semicarbazones. Why?
(ii)Why are aldehydesare more reactive than ketones when undergo nucleophillic addition reaction? (iii)During preparation of esters from a carboxylic acid and an alcohol in the presence of acid catalyst water or ester formed should be removed as soon as it is formed (iv)Why does methanal not give aldol condensation while ethanol gives?
(v)Why is the boiling point ofan acid anhydride higher than the acid from which it is derived 5
OR
(a) An organic compound ‘A’ with molecular formula C8 H8 O2 is reduced to 2- ethyl phenol on treatment with LiALH 4. ‘A’ forms a oxime with hydroxylamine and gives positive lodoform test and not a Tollen’s test. Identify the compound A and deduce its structure.
(b) Write the chemical equations for the following conversions:
(i) Ethyl chloride into propanoic acid
(ii) Benzyl alcohol into Benzoic acid
(iii) Acetone to tert-Butyle alcohol
Q25. (a) How will you bring about the following conversions
(i) benzene to 3-bromonitrobenzene
(ii) ethanol to but-1-yne
(iii) 1-bromopropane to 2-bromopropane
(b)Give a chemical test to distinguish between the following pairs of compounds:
(i) chlorobenzene and cyclohexylchloride.
(ii) vinyl chloride and ethyl chloride.
OR
(a) Give reasons for the following :
(i) The bond length of C–Cl bond is larger in haloalkanes than that in haloarenes.
(ii) Although alkyl halides are polar in nature but are not soluble in water
(b) Complete thye following equation
(a) Cr2 O7-- + H + + C2H5OH-----------
(b) XeF 4 + O2 F2 ----------
(c) 2H3 PO3 ----------^------ 5
Q 26. Give reasons for the following:
(a) ClF3 is known but Fcl3 does not known. ?
(b) Carbon show more catenation then phosphorous.?
(c) ICl is more reactive than I2 ?
(d)Drow the structure of N 205.
(e)Only Xe from inert gases make compound with O and F atom. While other gases does not. 5
OR
(a)2Mn4 – + 10 I – + 16 H– --------→
(b)2Mn4 – + H2O + I– --------- →
(c )Write complete chemical equations for
(i)Compare the oxidation of Fe2+ by Cr2O7 2– in acidic medium .
(ii) oxidation of Mn2+ by MnO4 – in neutral or faintly alkaline medium.( give support equation) (d)Cr2+ or Fe2+ (which one is stronger reducing agent)
thnk u so much sir u make chemistry easy for me
ReplyDeleteBy:- Ashish Dhaka