AHSEC| CLASS 12| CHEMISTRY| QUESTION PAPER - 2017| H.S. 2ND YEAR
2017
CHEMISTRY
Full Marks: 70
Pass Marks: 21
Time: Three hours
The figures in the margin indicate
full marks for the questions.
1. Mention the number of atoms in a b.c.c. unit cell. 1
2. Which of the following concentration of solution
depends on temperature?
(a) molality
(b) molarity
(c) mass %
(d) mole
fraction
3. Find out half-life time of a first order reaction with
rate constant k=2.31x10-14s-1. 1
4. Give one example of a biochemical catalyst. 1
5. Mention the type of ore that can be concentrated by froth
floatation process. 1
6. Give IUPAC name of the following compound:
7. Name the functional group of a compound that gives silver mirror test with Tollens’ reagent. 1
8. Name two bases present in DNA. 1
9. State Henry’s law.
At the same
temperature, CO2 gas is more soluble in water than O2 gas.
Which one of them will have higher value of KH? 2
10. Calculate the mass of a non-volatile solute of molar
mass 40g mol-1, which when dissolved in 114g octane to reduce its
vapour pressure to 80%.
11. For a reaction 2A – 4B + C, the concentration of B is
increased by 5.0x10-3 mol L-1 in 10 seconds. Calculate
the rate of disappearance of A. 2
12. Show that slope of the plot of Ink against 1/T is – Ea/R.
Give the graphical representation of the plot. 2
13. Name the main ore of iron.
How is cast iron
made from pig iron? 2
14. Define transition elements.
Given the
general electronic configuration of the transition elements. 2
15. Identify A and B in the following two reactions: 3
16. What is racemic mixture? Give one example. 2
17. (i) Arrange the following in decreasing order of their
basic strength: 1
C6H5NH2,
C2H5NH2, (C2H5)2NH,
NH3
(ii) Identify the organic product in the following reaction. Give its IUPAC name. 1
18. Name the following reactions: 2
19. (i) A compound forms h.c.p. structure. Calculate the
total number of voids in 0.5mol of it.
1
(ii) Atoms of
element B from h.c.p. lattice and those of the element A occupy 2/3rd
of tetrahedral voids. Determine the formula of the compound formed by the elements
A and B. 2
20. Explain the following observations: (any three) 1x3=3
(i) Sky appears
blue in colour.
(ii) Deltas are
formed where river meets the sea.
(iii)
Alum/ferric chloride solution is applied to stop bleeding.
(iv) Mist of fog
is formed in winter.
21. Give reasons for the following: (any three) 1x3=3
(i) Bleaching by
chlorine is permanent, while that by sulphur dioxide is temporary.
(ii) NH3
act as a Lewis base.
(iii) NO2
dimerises.
(iv) In the
reaction between HCI and powdered iron, ferric chloride is not formed.
22. (i) Name a transition element which does not
exhibit variable oxidation state. 1
(ii) Which of
the 3rd series of transition metals exhibit the largest number of
oxidation states? 1
(iii) Give
reason why HCL is not used to acidify KMnO4 solution in volumetric determination
of Fe2+. 1
23. (i) Write the IUPAC name of the following: 1
[Co(NH3)5CI]CI2
(ii) Draw the
geometrical isomers of the complex icon [Co(NH3)4CI2]+.
(iii) Fine the
secondary valency of Ni in [Ni(CO)4]
24. (i) Give reason why phenols are acidic in
nature. 1
(ii) Given one
general method of preparation 30 alcohol. Give equation. 1
(iii) Complete
the following reaction and name the product.
1
CH3 –
CH = CH2 + H2O H+
25. (i) What are non-essential amino acids? Give one
example. 1
(ii) Name one
vitamin which is not soluble in water and fat. 1
(iii) What is
the chemical basis of heredity. 1
26. (i) Give one example of addition
homopolymer. 1
(ii) Mention one
use each of LDP and HDP. 1
(iii) What is
the monomer unit of natural rubber?
1
27. Give one example of each of the following: (any
three) 1x3=3
(i) A tranquillizer
(ii) An antidepressant
drug
(iii) Narcotic
Analgesic
(iv) An
antiseptic
28. Answer (a) and (b), or (a) and (c):
(a) Define molar
conductivity of an electrolytic solution.
Show the
variation of molar conductivity of a strong electrolyte with square root of
concentration. 1+1=2
(b) Three
electrolytic cells A, B and C containing electrolytes ZnSO4, AgNO3
and CuSO4 respectively were connected in series.
A steady current
of 1.5A was passed through them. 1.45g Ag were deposited at the cathode of cell
B.
(i) How long did
the current flow? 1
(ii) What mass of
copper and zinc were deposited? 2
(At. Mass of Cu
= 63.5u, Zn = 65.3u and Ag = 108u)
Or
(c) State
Kohlrausch law.
The limiting
molar conductance’s of NaCl, HCL and CH3COONa are 126.45,426.16 and
91.OS cm2 mol-1 respectively at 298K. Calculate limiting
molar conductance of acetic acid at 298K. 1+2=3
29. Answer either (a) and (b), or (c) and (d):
(a) Give a
laboratory method of preparation of dinitrogen.
2
(b) Complete
the following chemical equations: 1+1+1=3
(i) Bg + N2
heat …..
(ii) Ma(N3)2
decomposition ……. + ……
(iii) (NH4)2Cr2O7
heat …… + …… + H2O
(c) Explain why
HNO2 behaves both as oxidising as well as reducing agent. 2
(d) Give
chemical equations for the following processes: 1x3=3
(i)
Decomposition of ozone at 523K.
(ii) Ozone oxidises
lead sulphide to lead sulphate.
(iii) Ozone
reacts with aqueous solution of potassium iodide to liberate iodine.
30. Answer the following: (any five) 1x5=5
(i) Give a general
method of preparation of aldehyde using a selective oxidising agent.
(ii) Give an
example of Clemmensen reduction reaction.
(iii) Identify the products A and B in the following reaction:
(iv) Write complete
chemical equation for the transformation of benzamide to benzoic acid.
(v) Arrange
the following in increasing order of acidity:
CH3COOH,
CH3CH2COOH, C6H5COOH, C6H5CH2COOH
(vi) Mention one
use of methanolic acid.
Or
An organic compound
X(C2H4O), on oxidation, gives Y(C2H4O2).
Compound (X) undergoes haloform reaction. On treatment with HCN, compound (X)
produces Z which on hydrolysis, gives 2- Hydro propanoic acid.
Identify X, Y and Z. Write the equation for the reactions involved. What
happens when X is treated with dilute NaOH?
***
CHEMISTRY SOLVED PAPERS PAGE LINK - Click here
BUY E-BOOK (PDF FILE)
[TO SEE FULL SOLUTION]
(Chapter wise Notes, Exam Question Papers solved, MCQ solved) [ARTS, COMMERCE, SCIENCE]
|
DOWNLOAD PAGE LINK:-CLICK HERE |
AHSEC PAGE LINK - CLICK HERE
Also Read: