Organisation : Bihar School Examination Board (BSEB)
Class : XII
Paper: Chemistry
Document Type : Model Question Papers
Year : 2017
Website : http://www.biharboard.ac.in/model-question-papers/
Download Question Paper : https://www.pdfquestion.in/uploads/10272-CHEMISTRY.pdf
Chemistry Model Question Paper :
Choose the correct answer :- (1 mark each)
1. The structure of a compound made of elements A and B is crystalised. atom ‘A’ is situated at the corners and atom ‘B’ is situated at the centre of each face of the cube. What is the formula of this compound?
(a) AB3
(b) A3B
(c) AB
(d) AB2
Related : BSEB Class XII Alternative English Model Question Paper 2017 : www.pdfquestion.in/10257.html
2.Which has maximum boiling point at one atmosphoric pressure ?
(a) 0.1 M NaCl
(b) 0.1 M BaCl2
(c) 0.1 M Sucrose
(d) 0.1 M Glucose
3. Faraday’s second law of electrolysis is related –
(a) with velocity of positive ions
(b) with atomic number of negative ions
(c) with atoms of positive ions
(d) with equivalent weight of electrolyte
4. The main source of helium is
(a) Radium
(b) Monazite
(c) Air
(d) Water
5. What is oxidation number of nickel in Ni(CO)4 ?
(a) 1
(b) 3
(c) 0
(d) 2
6. Which of the following does not form Hydrogen bonding ?
(a) NH3
(b) H2O
(c) HF
(d) HCl
7. The general formula of alkene is–
(a) CnH2n
(b) CnH2n–2
(c) CnH2n+2
(d) None
8. Isoprene monomer is present in which of the following?
(a) Natural rubber
(b) Terylene
(b) Nylon – 6, 6
(d) Polythene
9. The distillation of calcium formate, gives
(a) CH3CHO
(b) HCHO
(c) HCOOH
(d) CH3COOH
10. The unit for rate constant for a reaction is mole L–1sec–1. The order of the reaction is–
(a) 0
(b) 1
(c) 2
(d) 3
11. Spontaneous cell reaction will occur when
(a) E° is negative.
(b) G is negative
(c) DeltaG is positive.
(d) None of these
12. Fog is the colloidal system of-
(a) Gas in liquid
(b) Liquid in gas
(c) Solid in liquid
(d) Liquid in liquid
13. Which one of these is diamagnetic ?
(a) CO2+
(b) Ni2+
(c) Cu2+
(d) Zn2+
14. The O.S. of Fe in brown ring complex [Fe(H2O)5NO]SO4 is-
(a) + 1
(b) + 2
(c) + 3
(d) + 4
15. Ammonia is dried from
(a) Anhydrous CaCl2
(b) CaO
(c) Conc. H2SO4
(d) P4O10
16. Vitamin ‘C’ is
(a) Maleic acid
(b) Ascorbic acid
(c) Paracetamol
(d) Lactic acid
17. 1°, 2° and 3° alcohols are distinguished by
(a) Oxidation method
(b) Lucos test
(c) Victor Mayer test
(d) All
18. Which one is the most alkaline ?
(a) NH3
(b) CH3NH2
(c) (CH3)2NH
(d) (CH3)3N
19. Using inert electrode, electrolysis is done in the aqueous solution of sodium sulphate, What are the products obtained at cathode and at anode ?
(a) H2, O2
(b) O2, H2
(c) O2, Na
(d) O2,SO2
20. The half life period of a reaction is inversely proportional to the initial concentration.
The order of reaction is–
(a) 0
(b) 1
(c) 2
(d) 3
Very Short Questions :
Q. (a) Explain Raoult’s law.
(b) How is Raoult’s law a special condition of Henry’s law ?
2. 18 gm glucose is mixed with 178.2 gm water. What will be the V.P. of water in this solution at 100°C ?
3. How are metals purified by electrolytic method ?
4. What are the inter halogen compounds ? Determine the structure of BrF3.
5. How will you separate 1°, 2° and 3° alcohol by Lucas test ?
6. Differentiate the following–
(a) Acetaldehyde and Ketone
(b) Phenol and alcohol
7. Determine the equilibrium constant of following reaction–
8. What are the homogeneous and heterogeneous catalysts ? Explain with examples.
9. Write the IUPAC names of the following–
(a)CH – C – CH – CH – C – OH
10. Potassium permaganate is oxidising agent. Explain it with reactions.
Long Questions :
Q.1 (a) What do you mean by magnetic properties of solid substance.
(b) Explain the followings–
(i) Paramagnetism
(ii) Anti Ferromagnetism
(iii) Ferrimagnetism
(iv) Diamagnetism
Ans :
(a) Magnetic properties of solid – The magnetic properties of a substance depend upon magnetic moment of the substance. The matter is made of atoms. In atom, there is nucleus and electrons are revolving round the nucleus. The moving electron is considered as small electrid loop. This small electric loop produces magnetic field. This is the reason that there creates magnetic properties in solid substances.
(b) (i) Paramagnetism – That substance is called paramagnetic substance in which there is the presence of unpaired electrons. Such substances are weekly attracted by magnets. Ex – O2, Cu2+, Fe3+ etc.
ii) Antiferromagnetism – Those substances whose domains are oriented in opposite directions equally are called antiferromagnetic substances. Due to opposite orientations, mangnetic moments are cancelled.
iii) Ferrimagnetism – Those substances whose domains are orientated in parallel and antiparallel directions in unequal number are called ferrimagnetism. These substances are attracted weakly by magnetic fields
iv) Diamagnetism – Those substances in which pair electrons are present, are called diamagnetic substances. Those substances are repelled by magnets. Ex – C6H6, Zn2+,Sc3+ etc.
Q.2. (a) Explain Nernst equation for the determination of electrode potential in a Dariel cell.
(b) The rate constants of a reaction at 700 K is 2 mol L–1sec–1 and at 800 K, it is 32 mol L–1sec–1. Calculate activation energy.
Ans. :
(a) Nernst equation – In Daniel cell, the redox reaction take place. Consider a redox reaction as– A + B=L +M
Q.3. Convert the followings–
(a) Acetone from ethylalcohol
(b) Propionic acid from ethylbromide
(c) Ethylamine from methylamine
(d) Iodoform from acetone
(e) Ethylalcohol from methylalcohol