CLASS: B.Sc. CHEMISTRY
11N/ 148
St. JOSEPH’S COLLEGE (AUTONOMOUS) TIRUCHIRAPPALLI – 620 002
SEMESTER EXAMINATIONS – NOVEMBER 2011
TIME: 3 Hrs.
MAXIMUM MARKS: 100
SEM
SET
PAPER CODE
TITLE OF THE PAPER
V
2009
08UCH530208
ORGANIC CHEMISTRY – I
SECTION – A
Answer all the questions:
20 x 1 = 20
Choose the correct answer:
1.
2.
3.
4.
5.
2-propanol reacts with KBr and concentrated H2SO4 to give
a)
1-Bromo propane
b)
1,2 – Dibromopropane
c)
2-Bromo propane
d)
2,2 – Dibromopropane
The carbon atom of a carbonyl group is
a)
SP hybridised
b)
SP2 hybridised
c)
SP3 hybridised
d)
none of these
Napthalene undergoes oxidation with Na2Cr2O7 / H2SO4 to form
a)
Phthalic acid
b)
Benzoic acid
c)
Tetralin
d)
Phenylacetic acid
Which of the following is the strongest acid?
a)
Formic acid
b)
Trichloro acetic acid
c)
Acetic acid
d)
Trifluero acetic acid
Which of the following is least soluble in water?
a)
CH3OH
b)
CH3CH2OH
c)
CH3SH
d)
OHCH2CH2OH
Fill in the blanks:
6.
According to IUPAC system, Aryl halides are named as ______.
7.
Formalin is ______.
8.
Anthracene undergoes electrophilic substitution reactions mainly at ______ carbon.
9.
5% solution of acetic acid in water is known as ______.
10.
R-X + Mg
ehter
 ______.
reflex
State True or False:
11.
Alkyl halides undergo nucleophilic substitution reactions.
12.
Benzaldehyde will undergo Aldol condensation.
13.
All carbon atoms in anthracene is SP3 hybridized.
14.
Tartaric acid is present in grapes.
15.
Sulphanilamide is the compound from which other sulpha drugs are derived.
Match the following:
16.
Chlorobenzene
-
a) Moth – repellant
17.
CH3 – CHO
-
b) Ka = 17.7  10-5
18.
Napthalene
-
c) D.D.T
19.
Formic acid
-
d) Highly toxic
20.
Tetra ethyl lead
-
e) Ethanal
SECTION – B
Answer all the questions:
21.
a.
5 x 4 = 20
Discuss SN2 mechanism of alkyl halides.
OR
22.
b.
Write wurtz – fittig reaction and Ullmann reaction using examples.
a.
Give the physical properties of aliphatic carbonyl compounds.
OR
23.
b.
Illustrate benzoin condensation.
a.
How will you prepare napthalene from coal tar and petroleum.
OR
24.
b.
Draw the molecular orbital structure of anthracene.
a.
Write the preparation and uses of oxalic acid.
OR
25.
b.
Discuss mechanism of cleansing action of soap.
a.
How is ethyl mercaptax prepared from (i) ethyl iodide (ii) Ethanol?
OR
b.
Give the reaction of methyl lithium with (i) ethylene oxide (ii) acetaldehyde.
SECTION – C
Answer any FOUR questions:
26.
4 x 15 = 60
i). Write the reactions of Ethyl bromide with the following
(10)
(a) KOH
(b) Sodium ethoxide (c) NaCN
(d) K2S
reactants
(e) KSH
ii). Explain electrophilic aromatic substitution reaction mechanism of halobenzene
(5)
27.
i). Explain the reactions of acetaldehyde with the following
(a) NaHSO3 (b) NH2 – NH – C6H5
reactants
(c) CH3 – CHO (d) Cl2
(e) H2 / Ni
ii). Write short notes on acidity of alpha hydrogen.
28.
i). Discuss structural elucidation of napthalene.
(10)
ii). What happens when anthracene is treated with
(a) Bromine in CCl4 (b) nitric acid and acetic acid
29.
(5)
i). Write the reactions of acetic acid with the following reactants.
(a) NaHCO3 (b) NH3 (c) C2H5OH (d) LiAlH4 / Ether (e) Cl2 (10)
ii). How is soap manufactured by hydrolyser process?
30.
i). How is saccharim prepared?
(5 + 5 + 5)
ii).Write the preparation and uses of benzene sulphonyl chloride.
iii). What happens when methyl magnesium iodide is treated with
Propyne
**************
(a) water
(b)