West Bengal Institute of Technology (WBIT) 2008-2nd Sem B.Tech Computer Science and Engineering Computer Science - Chemistry - Question Paper
tMtWbVBiXr u MAiMSjsmm examinations, jxjne - 2008 GXKEJTRING CHEMISTRY
SEMESTER - 2
[ Full Mark;. : 70
Time : 3 lit a.s ]
GROUP-A ( Multiple Choice Type Questions )
10 x 1 = 10
1. Choose the currtct alternatives lor any ten of the following :
i) A living system is the i mo chmamically an example of
a) an isolated system b) a closed system
c) an adtabutieally closed system d) an open system.
ii) For an ideal gas undergoing free expansion
a) AT = 0 and AS > 0 b) AT = 0 and AS = C
c) AT < 0 anti AS > 0 d) AT < 0 arid AS * 0.
iii) Structure of SF 6 is
|
a) planar c) trigonal bipyramidal |
b) octahedral d) square pyramidal. |
iv) Two eL*meniJ, whose electronegativities are 1*2 aad 3 0, form
|
uj n.; I 0 .d c) co-cr'lnate bond v) Germanium id an ex air.pk; of a) intrinsic semiconductor c) p-typc semiconductor |
b) covalent bond d) metallic bond. b) n-type semiconductor d) insulator. |
f V.c'A..ni, . 4 " -o'V
vi) Proton NMR is useful for Investigating structure jf orgrtWc molecules because
a) organic molecules contain carbon atoms
fc) organic molecules are mostly covalent
c) hydrogen atoms are found in most of the organic molecules
d) organic compounds are low boiling. |__
.ii; Hit; half-life of a first order reaction is 20 minutes. The time req completion of the reaction is
for 7
-L Vi.
b)
d)
40 minutes 60 minutes.
30 minutes 50 minutes
a1 c)
l____ . J
viii) \V1aioh one has the largest bond angle ? a) H90 b)
H2S
c) PH,
d)
NH3.
Which of the octahedral complexes ( M metal atom, A and B are l.g me. i ) exhibits geometrical isomerism ?
!x)
a) IMA6 ] c) [MA 4B2 ]
't iic; most stable carbonium ion is
a} (CH3)2CH+ *
IMA5B
b)
d)
b)
ti)
]
MA3B3].
x)
Ph3C+
J
ch3 ch2+
CH2 a ch - ch2+.
xi) An (example of tliermosetting plastic is
PVC b)
c) polythene d)
xii) lne calorific value is highest for
a) water gas b)
c) producer gas d)
nylon
bakelite,
LPG
carburetted water gas.
::
::
\ ri~2:a8d6~(t;n
GROUP-B ( ihori Answer Type guestions )
3x5=15
Answer any three of the following.
2. Show that for an ideal gas undergoing reversible adiabaio expansion or compression PV Y = constant. A diatomic ideal gas ( y = 1-4 ), fni.al'iy at 800 K and .10 .atm undergoes reversible adiabatic expansion till the final pressure becomes 2 atm. FU:d
cut its filial volume.
3. Explain why uia anion [ CoF6 ] 3 " is paramagnetic while .the anion J Co ( CN ) 6 J 3 is diamagnetic.
4. Write down the Arrhenius equation for the temperature dependence of specific rate
explain the terms i-sed. What is the unit of the frequency factor for a first order reaction ? Plot log k vs and explain the significance of toe slope of the plot.
5. Predict the shape of the following molecules using VSEPR theory :
BF 0 , CO,, , PCI 5 , SF 6 , XeF 4 .
6. Account for the following :
i) SN 2 reaction occurs with inversion of configuration and SN1 reaction occurs with re U;. ition of configuration.
Li Formic acid is more acidic than acetic acid and acetic acid is more acidic than
phene],
GROUP -C ( Long Answer Type Questions *
3x15- 45
Answer any three questions.
3
7. a) What are raw rubber aiid vulcanized rubber ?
6
b) Give the outlines of preparation, structure and uses of SBR and NBR.
c) Explain number average and weight average molar mass of a polymer.
d) Define intrinsic and extrinsic semiconductors.
11-222855 (5)
i
b. a) ,hiit is meant by transport number of an ion ? Hew is it related with ion conductance ? The ionic radius of Li+ is less than t iat of K \ However, aqueous solution Li+ ions are less mobile than K + lens. How can you explain th
observation ? 1 + 1,
b) Draw the conductometric titration curve for HCI us NH 4 OH and explai i ti tea tares of the curve.
c) 'What do you mean by half-decomposition period of a reaction ?
Consider a second order reaction A + B -> products. Assuming the i iiti; concentrations of both the reactants Lo be s.ui.e. show that the ha< decomposition period of the reaction is inversely pruportional to the init. concentration. 1 +
d; Rate constants of a reaction at 300 K and 310 K are 4-5 x 10 " 5 s~ 1 ai 9 x 10" 5 s' 1 respectively. Evaluate the activation energy and the pre-exponen factor ( frequency factor ) of the reaction. What is the order of the reaction ?
L
O
a) Explain optical isomerism in case of co-ordination compounds with sukab. examples.
b) Write down the order of the bond energy of the following bonds and give reas for your answer :
C = 0, C = N, C - I, C - F.
c) jSxpk-Jn the term 'hyperconjugation', citing examples.
d; Distinguish between coking coal and caking coal.
a) How do the properties such as (i) tensile strength (ii) physical state of polymer (iii) impact strength (iv) melt viscosity of a polymer vary with degree polymerization?
b) Discuss the difference among isotactic, syndio tactic and atacic polymers.
c) Degree of polymerization of a sample of polymethylmethacrylate ( PM vl-v ) found to be 1000, What is the number average and the weight average .no., masses of PMMA ?
dj What is the importance of 'functional group region' in IR spectroscopy ? WL are the different absorption peaks possible for methumol and ethanol ? I t
 |
|
3x5 |
11. Wrile notes on any three uf Hit following :
a) Joule-Thomson expansion and inversion temperature.
b) Chemical potential and its significance in explaining equilibrium of reacting
sy stems.
c) Hydrogen bouding and its effect on properties of coiupouuda. d| Non-stoichiometric defects.
e) Carbureted water gas and semi-water gas
f) Perfect aud imprfect complexes.
END
H-222855 (SY i
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Attachment: |
| Earning: Approval pending. |
