Indian Journal of Chemistry
Sect. A: Inorganic, Bio-inorganic, Physical, Theoretical & Analytical
VOLUME 41A
NUMBER 5
MAY 2002
CONTENTS
Papers
893
The largest eigenvalues of adjacency and
Laplacian matrices, and ionization potentials
of alkanes
The largest eigenvalue 1 of the Laplacian matrix of
molecular graphs is correlated with the largest eigenvalue
1 of the adjacency matrix. The correlation is linear, but the
data points are grouped depending on the presence (d max =4)
or absence of quaternary carbon atoms (d max =3 & dmax =2).
This implies that the first ionization of C2s electrons takes
place at quaternary carbon atom (requiring less energy) or,
when such carbon atoms are not present, from a tertiary
carbon atom (requiring more energy).
Ivan Gutman* & Dušica Vidović
897
Self consistent field molecular orbital studies
on chlorinated cumulenes
R Amrutha, L Sangeetha &
P Chandran*
904
Energy volume coefficient of solutions
involving amides, H2O and D2O at
298.15 K
K J Patil*, R B Pawar, S S Dighe &
S N Deshmukh
914
Effect of organic counter-ions on the surface
activity, micellar formation and dye
solubilization behaviour of cationic surfactants
Sujata Sinha, P Bahadur &
Nirmesh Jain*
A systematic study of chlorination on cumulenes is reported
in the present study. Chlorination leads to an increased pz
orbital occupation of inner carbon atoms. Using finite
perturbation technique, proton coupling constants of
butatriene are also calculated.
Sound velocities at 298.15 K and densities at different
temperatures of aqueous solutions of formamide,
acetamide, propionamide, DMF and DMAC have been
measured in the concentration range ~ 0.2 - 2.0 m.. The
variation of energy volume coefficient in H2O and D2O
systems and the trends in limiting transfer properties have
been interpreted in terms of effects of amides on the water
structure through H-bonding and hydrophobic interactions.
The effect of organic counter-ions, (aliphatic, both mono
and dicarboxylates), on the surface and micellar behavior of
decyl and dodecyl ammonium carboxylates in aqueous
solution has been examined using surface tension, dye
solubilzation, conductance viscosity and nuclear magnetic
resonance. The decrease in CMC and increase in counterion binding of cationic surfactants is attributed to the
increased hydrophobicity in alkyl chain of counter-ions.
921
Electrochemical characterization of a Dowex-50 membrane
has been described on the basis of mixed membrane
potential and conductance measurements. It is shown that
thermodynamic considerations can be used with advantage
to derive permselective behaviour of the membrane even
when electrolyte mixtures are used. Observed variation in
permselectivity with composition of NaCl and KCl mixture
is explained in terms of alteration in co-ion exclusion as a
result of accompanying swelling/deswelling of the
membrane matrix
Mixed membrane potentials and
electrochemical characterization of
membranes
Kehar Singh*, A K Tiwari &
Chandra Shekhar Dwivedi
928
Liquid-phase Friedel-Crafts acylation using
NixMn(1-x)Fe2O4 spinel catalysts
S Sugunan*& K Nishamol
934
Heavy metal ion uptake by homo and
copolymers – A comparative study
K Hussain Reddy* &
A Ravikumar Reddy
942
Synthesis, spectral, redox and biological
studies of some Schiff base copper(II),
nickel(II), cobalt(II), manganese(II), zinc(II)
and oxovanadium(II) complexes derived from
1-phenyl-2,3-dimethyl-4(4-iminopentan-2-one)
pyrazol-5-one and 2-aminophenol/2-aminothiophenol
N Raman*, A Kulandaisamy &
K Jeyasubramanian
Notes
950
Stereochemical and compositional assignments
of acrylonitrile/butylacrylate copolymers by
two-dimensional NMR spectroscopy
Acrylonitrile/butylacrylate copolymers have been prepared
by bulk polymerization using benzoyl peroxide as initiator.
2D-heteronuclear single quantum correlation (HSQC) and
total correlated spectroscopy (TOCSY) spectra have been
used to resolve the complex 1H NMR spectrum and to
determine the compositional and configurational sequences
of the copolymers
A S Brar & D R Pradhan
955
Hydrogen production by water
electrolysis using solid polymer electrolyte
Sang-Do Han, K C Singh*, R K Rana &
Kee-Bae Park
Electro- catalysts platinum and iridium are deposited
on Nafion-117 membrane by chemical deposition
method. The minimum loading of Pt and Ir required
on SPE for efficient working of electrolysis cell are
found to be between 1.15mg/cm2 and 2.8mg/cm2
respectively. The cell voltage has been found to
decrease with increase in temperature.
960
Potentiometric studies on the protonation
constants and solvation of some -amino acid
methyl- and ethyl esters in ethanol-water
mixtures
Alev Doğan , Fitnat Köseoğlu &
Esma Kılıç
963
Preparation of phthalimide by ammoxidation
of o-xylene and characterization of V-CrO/SiO2 catalyst
Xie Guangyong, Zheng Qiong*,
Huang Chi &Chen Yuanyin
967
Kinetics of reduction of triaminotolyl diphenylmethane chloride (rosaniline
hydrochloride) by hydroxide ions in aqueous
medium
J F Iyun, A O Peters & O A Babutunde*
970
Novel synthesis of allyl and cyclopropylcarbinyl thiocyanates by the reaction of
organocobaloximes with thiocyanogen
B D Gupta*, Debprasad Mandal &
Vandana Dixit
The stoichiometric protonation constants of methyl- and
ethyl esters of glycine, L-alanine, L-valine, L leucine,
L-phenylalanine, L-serine, L-methionine and methyl ester of
L -isoleucine in 20-80 % (v/v) ethanol-water mixtures and
the effect of solvent on -amino acid methyl- and ethyl
esters have been determined at 25C under nitrogen
atmosphere. The variation of the protonation constants is
discussed on the basis of specific solute-solvent
interactions.
O
V-Cr-O/SiO2
CH3
+ NH3 + 3O2
CH3
NH + 4H2O
O
973
Synthesis, characterization and
electrochemical properties of Fe(III)
binuclear complexes
C A Sureshan & P K Bhattacharya*
976
Synthesis and characterization of nicotinic acid
coordinated metal carbonyl complexes
Reflux,Ar
M(CO)6 + CH3CN
excess

8h, M=Mo
48 h, M= W
D Jesudurai & S Vancheesan*
fac-[M(CO)3(CH3CN)3]
in situ
 NIC/EtOH
(3 equiv.)
 RT,1h
fac-[M(CO)3(NIC)3]
981
Adsorptive stripping voltammetric
determination of nickel (II) using
N-2-pyridylbenzamidine as a complexing
reagent
An adsorptive stripping voltammetric method for the trace
measurement of nickel(II) based on the use of N-2pyridylbenzamidine as the complexing agent at hanging
mercury drop electrode in 0.8 M NH4Cl / NH3 buffer of
pH 9.6 is described.
R K Mahajan* & P Dhawan
985
Extractive determination of cobalt (II) using
tri-iso-octylamine
H K Mondal, B Sarkar & S Basu*
988
Rapid spectrophotometric determination of
platinum(IV) using piperonal
thiosemicarbazone
Prakash Shetty, A Nityananda Shetty &
R V Gadag
991
Preconcentration and determination of trace
amounts of heavy metals in natural water
samples using a C18 cartridge and atomic
absorption spectrometry
Y Yamini*, H Ebrahimzadeh & M Chaloosi
996
Liquid-liquid extraction of tin (IV) with
Cyanex 302
Sunil G Sarkar  Purushottam M Dhadke*
A selective and quantitative exraction method for the
determination of cobalt(II) using tri-iso-octylamine (TIOA),
a high molecular weight tertiary amine, into cyclohexane
from aqueous hydrochloric acid medium has been
developed
A simple, rapid, selective and sensitive spectrophotometric
method for the determination of platinum has been
proposed based on the colour reaction between
platinum(IV) and piperonal thiosemicarbazone (PATS) in
0.008 - 0. 032 M sulphuric acid medium.
A rapid and reliable sample preconcentration method has
been developed to separate Ni2+, Bi3+, Cd2+, Fe3+, Pb2+,
Zn2+, Cu2+and Co2+ (heavy metal ions) from natural water
samples. The chelating agent sodium diethyldithiocarbamate (SDDTC) and a C18 cartridge have been used for
preconcentration.
A method for liquid-liquid extraction of Sn(IV) has been
proposed. The optimum extraction conditions have been
evaluated by studying parameters like acidity, extractant
concentration, period of equilibrium, effect of diluents and
effect of diverse ions.
999
Fluoride estimations in water using ion
selective electrode: Choice of appropriate
TISAB
Meetu Agarwal, Kavita Rai, Rohit Shrivastav
& Sahab Dass*
The efficacy of ten different TISABs for fluoride estimation
in water samples in presence of F- binding cations, viz.,
Al3+ and Fe3+, has been investigated. The study suggests
that the TISAB, containing tris - hydroxymethyl
aminomethane hydrochloride buffer is probably best suited
for F- estimation in samples, especially, in presence of high
concentrations (1-2 g dm-3) of Al3+.
Authors for correspondence are indicated by (*)
Indian Journal of Chemistry
Vol. 41A May 2002, pp 893-896
The largest eigenvalues of adjacency and Laplacian matrices, and
ionization potentials of alkanes
Ivan Gutman & Dušica Vidović
If G is a molecular graph and A(G) its adjacency matrix, then the
Laplacian matrix is defined as
L(G)=D(G)-A(G) where D(G) is the diagonal matrix of vertex degrees. We establish a relation between the largest
eigenvalues of A(G) and L(G) in case of the molecular graphs of alkanes. This relation is linear, but differs for alkanes
with and without a quaternary carbon atom, revealing the main features of the structure-dependence of their (first)
ionization potential. An analogous, yet more general, relation holds for all trees.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 897-903
Self consistent field molecular orbital studies on
chlorinated cumulenes
R Amrutha , L Sangeetha & P Chandran*
Cumulenes are compounds containing a unit of ‘n’ carbon atoms with (n-1) double bonds between
them (n>3).The members are propadiene(allene), butatriene, pentatetraene etc. A systematic study of
chlorination on cumulenes is done in the present study. Geometrical optimisation is carried out on the
cumulenes using RHF wave functions with 31-G basis set using Gaussian –94. Semi-empirical
calculations(CNDO/2) are performed to elicit the trend of chlorination. Chlorination of cumulenes brings
out some interesting properties such as lowering of energy, redistribution of charge density, stability of
odd number of double-bonded cumulenes, etc. The ionisation potential of odd number of double bonded
cumulenes are high compared to that of even number of double bonded cumulenes. To study the trend of
redistribution of charge densities due to chlorination it is sufficient to substitute a single chlorine atom .
The inner carbon atoms distribute their electronic charges in the direction of chlorinated carbon atoms.
Chlorination leads to an increased pz orbital occupation of inner carbon atoms. Using finite perturbation
technique , proton coupling constants of butatriene are also calculated.
Indian Journal of Chemistry
Vol. 41A May 2002, 904-913
Energy volume coefficient of solutions involving amides, H2O and
D2O at 298.15 K
K J Patil*, R B Pawar, S S Dighe & S N Deshmukh
Sound velocities at 298.15 K and densities at different temperatures of aqueous solutions of amides
(formamide, acetamide, propionamide, DMF and DMAC) have been measured in the concentration range
~ 0.2 to 2.0 m. The experimental data have been used to calculate the thermodynamic parameters like
apparent molar volume (v), apparent molar isothermal compressibility (T) of solutes at various
concentrations and energy volume coefficient (dU/dV)T of solutions at different amide concentrations in
H2O as well as in D2O solutions. From the infinite dilution properties (v0 and T0), the transfer volumes
and transfer compressibilities for the transfer of amides from H 2O to D2O solvent system have been
calculated. The variation of energy volume coefficient in H2O and D2O systems and the trends in limiting
transfer properties are examined and have been interpreted in terms of effects of amides on the water
structure through H-bonding and hydrophobic interactions.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 914-920
Effect of organic counter-ions on the surface activity, micellar
formation and dye solubilization behaviour of cationic surfactants
Sujata Sinha, Nirmesh Jain* & P Bahadur
The effect of eight organic counter-ions (aliphatic, both mono and dicarboxylates) on the surface and
micellar behavior of decyl and dodecyl ammonium carboxylates in aqueous solution has been examined
by different physico-chemical techniques such as surface tension, dye solubilzation, conductance viscosity
and nuclear magnetic resonance. The effect of these counterions as observed from surface activity, and
critical micelle concentration (CMC) is explained in terms of their condensation /penetration onto/into the
micelles. The decrease in CMC and increase in counter-ion binding of cationic surfactants is attributed to
the increased hydrophobicity in alkyl chain of counter-ions. In the case of monocarboxylate counter-ions,
CMC decreases significantly in the order : n-butyrate < propionate < acetate <formate, while for
dicarboxylates decrease in CMC with increase in number of carbon atoms in the counter-ion is very less
substantial. Compared to monocarboxylates, dicarboxylate counter-ions condense strongly onto the
micelle surface and thus are capable of being easily incorporated into the micelles and consequently show
greater surface activity, and lower CMC of cationic surfactant. The effect of temperature on surface
activity and micellar behavior of decyl ammonium succinate is also reported.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 921-927
Mixed membrane potentials and electrochemical characterization
of membranes
Kehar Singh*, A K Tiwari & Chandra Shekhar Dwivedi
Mixed membrane potential and membrane conductance measurements have been carried out using
Dowex-50 membrane and sodium chloride and potassium chloride solutions of variable composition with
the object of electrochemical characterization of the membrane system. The data were examined in the
light of thermodynamic considerations to obtain transport numbers of the ions in the membrane phase for
the estimation of permselectivity. Variation of these electrochemical parameters with composition of the
electrolyte mixtures has also been examined. The results show that the presence of additional electrolyte
even if its concentration is same on both sides of the membrane, significantly influences electrochemical
character of the membrane.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 928-933
Liquid-phase Friedel-Crafts acylation using NixMn(1-x)Fe2O4 spinel
catalysts
S Sugunan*& K Nishamol
The liquid-phase Friedel-Crafts acylation of toluene using benzoyl chloride as benzoylating agent has been carried
out over Nix Mn(1-x) Fe2 O4(x=0, 0.2, 0.4, 0.6, 0.8 and 1.0) type systems under different reaction conditions. It is
observed that the systems with high ‘x’ values are effective for the conversion of BOC and the selective formation of 4MBP. Selectivity for 4-MBP over MnFe2O4 is more than 90% under the optimized reaction conditions. Sites of
moderate acidity is effective in catalyzing the benzoylation reaction.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 934-941
Heavy metal ion uptake by homo and copolymers – A comparative
study
K Hussain Reddy* & A Ravikumar Reddy
Homo and copolymers of 2-hydroxy
ethyl methacrylate and chloromethylated styrene-anthranilic acid have been prepared by free radical
polymerization technique. The chelating polymers have been characterized by IR and solid state 13C
NMR spectroscopic techniques.
Thermal stabilities of these polymers are investigated using
thermogravimetric and differential thermal analyses. Heavy metal ions viz., Pb(II), Hg(II), Cd(II) and
Cr(VI) have been removed by employing the present chelating polymers. Metal ion uptake efficiency,
effect of pH and time on the metal removal have also been studied. The metal removal properties are also
tested under competitive conditions and found to depend strongly on pH. The polymers possess
appreciable selectivity for Pb(II) and Hg(II) over Cd(II) and Cr(VI). The amount of metal uptake by the
polymer has been determined using atomic absorption spectrophotometer. The polymers have been
reused after desorbing the metal ion from the polymer metal complex by HCl.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 942-949
Synthesis, spectral, redox and biological studies of some Schiff base
copper(II),nickel(II), cobalt(II), manganese(II), zinc(II) and
oxovanadium(II) complexes derived from 1-phenyl-2,3-dimethyl-4
(4-iminopentan-2-one) pyrazol-5-one and 2-aminophenol/
2-aminothiophenol
N Raman*, A Kulandaisamy & K Jeyasubramanian
Neutral tetradentate complexes of Cu(II), Ni(II), Co(II), Mn(II), Zn(II) and VO(II) have been
synthesised using new Schiff bases derived from 2-aminophenol/2-aminothiophenol and 1-phenyl-2,3dimethyl-4(4-iminopentan-2-one)-pyrazol-5-one in ethanol and characterized by microanalytical data, IR,
UV-Vis., 1H NMR and ESR spectra. Non-electrolytic behaviour and monomeric type of the chelates have
been assessed from their low conductance and magnetic susceptibility values respectively. The IR and
UV-Vis. spectra suggest that all the complexes have square planar geometry except vanadyl and
manganese complexes which show square pyramidal and octahedral geometry respectively. The redox
behaviour of copper and vanadyl complexes has been studied by cyclic voltammetry and the ESR spectra
of copper and vanadyl complexes are recorded and discussed. Antimicrobial activity of the Schiff bases
and their complexes have been extensively studied on some microorganisms like Staphylococcus aureus,
Bacillus subtilis, Klebsiella pneumoniae, Salmonella typhi, Pseudomonous aeruginosa, Shigella flexneri,
Aspergillus niger and Trichoderma viridi. Most of the complexes have higher activity than the free ligand.
Notes
Indian Journal of Chemistry
Vol. 41A May 2002, pp 950-954
Stereochemical and compositional assignments of
acrylonitrile/butylacrylate copolymers by two-dimensional
NMR spectroscopy
A S Brar & D R Pradhan
Acrylonitrile/butylacrylate (A/B) copolymers have been prepared by bulk polymerization using benzoyl peroxide as
initiator. 2D-heteronuclear single quantum correlation (HSQC) and total correlated spectroscopy (TOCSY) spectra
have been used to resolve the complex 1H NMR spectrum and to determine the compositional and configurational
sequences of A/B copolymers.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 955-959
Hydrogen production by water electrolysis using solid polymer
electrolyte
Sang-Do Han, K C Singh*, R K Rana & Kee-Bae Park
Electro- catalysts platinum and iridium are deposited on solid polymer electrolyte [(SPE) i.e. Nafion117] membrane by chemical deposition method. The minimum loading of Pt and Ir required on SPE for
efficient working of electrolysis cell are found to be between 1.15mg/cm 2 and 2.8mg/cm2 respectively.
The best hydrothermal treatment temperature is found to be between 110C and 120C. The effect of the
operating temperature on the cell performance is also studied. The cell voltage has been found to decrease
with increase in temperature.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 960-962
Potentiometric studies on the protonation constants and solvation
of some -amino acid methyl- and ethyl esters in ethanol-water
mixtures
Alev Doğan, Fitnat Köseoğlu & Esma Kılıç
The stoichiometric protonation constants of 15 esters (methyl- and ethyl esters of glycine, L- alanine,
L-valine, L-leucine, L - phenylalanine, L -serine, L -methionine and methyl ester of L -isoleucine) in 2080 % (v/v) ethanol-water mixtures and the effect of solvent on -amino acid methyl- and ethyl esters have
been determined at ionic strength of 0.1 M NaCl and at 25C under nitrogen atmosphere. A potentiometric
method is used and the calculation of constants has been carried out using PKAS computer programme.
The logarithm of the protonation constants of -amino acid esters decreases linearly with increase in
ethanol contents. The variation of these constants is discussed on the basis of specific solute-solvent
interactions.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 963-966
Preparation of phthalimide by ammoxidation of o-xylene and
characterization of V-Cr-O/SiO2 catalyst
Xie Guangyong, Zheng Qiong*, Huang Chi & Chen Yuanyin
Phthalimide, as an important intermediate of organic synthesis, has been prepared with high yield by
ammoxidation of o-xylene over silica-supported vanadium-chromium oxide catalysts. Under suitable
conditions, the molar yield of phthalimide can reach 89% with purity of 98.6%. The catalysts, prepared
via wet-impregnation method, have been characterized by BET, XPS and XRD. Results show that vanadia
and chromia form composite oxides, which exist mostly in the pores of silica. Their concerted catalytic
function is the main reason for high activity. Vanadium exists mainly as pentavalent and chromium mainly
as trivalent in the V-Cr-O/SiO2 catalysts, with their oxidation states changing in the redox cycles. The
additive chromium can interact with the surface vanadium oxide phase and alter the structure of vanadia,
which delays the formation of crystalline V2O5 and increases the catalytic activity and selectivity.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 967-969
Kinetics of reduction of triaminotolyl -diphenylmethane chloride
(rosaniline hydrochloride) by hydroxide ions in aqueous medium
J F Iyun, A O Peters & O A Babutunde*
Kinetics and mechanism of reduction of rosaniline hydrochloride (RH) by hydroxide ions have been studied in
aqueous medium at 30C at ionic strength of 1.0 mol dm-3 (NaCl).
The reduction follows a second order kinetics and it conforms to the rate law:
d
[RH] = k2 [RH][OH-] and k2 is
dt
found to be 1.84  0.04  102 mol dm-3 min-1.
The rate of reaction is not sensitive to changes in dielectric constant of the medium and free radicals have not been
detected in the reaction. The rate of reaction decreased with increase in ionic strength. The results from our
spectroscopic investigations and Michaelis-Menten analysis do not show any evidence for an intermediate of
significant stability. The outersphere mechanism is, therefore, postulated for this reaction.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 970-972
Novel synthesis of allyl and cyclopropylcarbinyl thiocyanates by
the reaction of organocobaloximes with thiocyanogen
B D Gupta*, Debprasad Mandal & Vandana Dixit
Thiocyanogen reacts in aprotic solvents with allyl and but-3-enyl cobaloximes to give moderate yields
of allyl and cyclopropylcarbinyl thiocyanates. Using this method highly unstable allyl thiocyanates may
be prepared in situ at low temperature. Their rearrangement to isothiocyanates is observed at sub-zero
temperatures.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 973-975
Synthesis, characterization and electrochemical properties of
Fe(III) binuclear complexes
C A Sureshan & P K Bhattacharya*
Ternary binuclear complexes (AFeL'FeA) Cl4 where L1 is the binucleating ligand 5,5-methylene-bissalicylaldehyde and ligand A is 2,2-bipyridyl or 1,10-phenanthroline, and binary binuclear complexes of
the binucleating schiff base with two tridentate coordination sites, obtained by the condensation of 5,5methylene-bis-salicylaldehyde with aminoethyl pyridine, have been synthesized and characterized by
spectral, magnetic, mass spectral and electrochemical studies.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 976-980
Synthesis and characterization of nicotinic acid coordinated metal
carbonyl complexes
D Jesudurai & S Vancheesan*
Two zero-valent metal carbonyl complexes fac-[M(CO)3(NIC)3] (where M = Mo, W; 3, 4; NIC = 3HO2CC5H4N) have been synthesized and characterized by elemental and thermal analysis ( TGA, EGA ),
IR and powder X-ray diffraction ( XRD ) spectroscopic techniques. The IR spectrum of complex 3
exhibits three CO stretching bands and 4 shows two CO stretching bands in addition to a carboxyliccarbonyl stretching band. The possibility of fac / mer isomerization in complex 3 has been studied by IR
spectroscopy in various solvents. Elemental and mass spectrometric data are consistent with the formation
of the title complexes. The powder X-ray diffractogram of complexes 3 and 4 exhibit similar pattern
suggesting the same geometry.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 981-984
Adsorptive stripping voltammetric determination of nickel (II)
using N-2-pyridylbenzamidine as a complexing reagent
R K Mahajan* & P Dhawan
An adsorptive stripping voltammetric method for the trace measurement of nickel(II) based on the use
of N-2-pyridylbenzamidine as the complexing agent at hanging mercury drop electrode in 0.8 M NH4Cl /
NH3 buffer of pH 9.6 is described. Variable factors affecting the response, i.e., the concentration of
ligand, pH, adsorption potential and adsorption time are assessed and optimized. The calibration curve for
nickel(II) is linear over the range 5.0 x10 – 9 – 5.0 x 10 –8 M with accumulation time of 180 s at –0.4 V vs
Ag/AgCl. The method has been applied for the determination of nickel(II) in urine samples of exposed
workers of nickel plating industries.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 985-987
Extractive determination of cobalt (II) using tri-iso-octylamine
H K Mondal, B Sarkar & S Basu*
A selective and quantitative exraction method for the determination of cobalt(II) using tri-isooctylamine (TIOA), a high molecular weight tertiary amine, into cyclohexane from aqueous hydrochloric
acid medium has been developed. The effects of concentration of HCl, extractant, metal ions, role of
various diluents and diverse ions on the extraction of cobalt have been studied. The method has been
successfully applied to the estimation of cobalt in several ores and pharmaceutical drug samples.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 988-990
Rapid spectrophotometric determination of platinum(IV) using
piperonal thiosemicarbazone
Prakash Shettya, A Nityananda Shetty & R V Gadag
A simple, rapid, selective and sensitive spectrophotometric method for the determination of
platinum has been proposed based on the colour reaction between platinum(IV) and piperonal
thiosemicarbazone (PATS) in 0.008 - 0. 032 M sulphuric acid medium. The greenish yellow complex has
an absorption maximum at 360 nm. Beer’s law is obeyed upto 6.5 ppm of Pt and the optimum
concentration range is 1 - 5.1 ppm of Pt. The molar absorptivity and Sandell’s sensitivity are 3. 239  104
l mol-1 cm-1 and 0.006 g cm-2, respectively. The optimum conditions for complete colour development
have been investigated by studying parameters like effect of medium, acidity, reagent concentration, time
period and effect of diverse ions. The method is used for the determination of platinum in hydrogenation
catalysts and platinum complexes.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 991-995
Preconcentration and determination of trace amounts of heavy metals in
natural water samples using a C18 cartridge and atomic absorption
spectrometry
Y Yamini*, H Ebrahimzadeh & M Chaloosi
A rapid and reliable sample preconcentration method has been developed to separate Ni 2+, Bi3+, Cd2+,
Fe3+, Pb2+, Zn2+, Cu2+and Co2+ (heavy metal ions) from natural water samples. The chelating agent
sodium diethyldithiocarbamate (SDDTC) and a C18 cartridge have been used for preconcentration.
Extraction efficiency, influence of sample and eluent flow rates, pH, amount of SDDTC, nature and
amount of eluent for elution of metal ions from cartridge, break through volume and the limit of detection
have been evaluated. The effects of alkali and alkaline earth metal ions on percent recovery of heavy
metal ions have also been studied. The limit of detection of the proposed method for Ni 2+, Bi2+, Cd2+,
Fe3+, Pb2+, Zn2+, Cu2+and Co2+ are found to be 1.5, 5, 0.4, 3, 2.5, 0.6, 0.5 and 1 ppb, respectively. The
method is applied to the recovery and determination of heavy metal ions in different water samples.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 996-998
Liquid-liquid extraction of tin (IV) with Cyanex 302
Sunil G Sarkar  Purushottam M Dhadke*
A method for liquid-liquid extraction of Sn(IV) has been proposed. Tin (IV) is extracted from
hydrochloric acid solution of 0.25 mol dm3 with 5102 mol dm3 Cyanex-302 in toluene, followed by
spectrophotometric determination of Sn(IV) after stripping the non-aqueous phase with 4.0 mol dm3
perchloric acid by Morin method. The optimum extraction conditions have been evaluated by studying
parameters like acidity, extractant concentration, period of equilibrium, effect of diluents and effect of
diverse ions. The method has been applied for the determination of Sn (IV) in real samples.
Indian Journal of Chemistry
Vol. 41A May 2002, pp 999-1002
Fluoride estimations in water using ion selective electrode: Choice
of appropriate TISAB
Meetu Agarwal, Kavita Rai, Rohit Shrivastav & Sahab Dass*
Choice of appropriate TISAB (total ionic strength adjusting buffer) plays a crucial role in fluoride (F-)
analysis in water samples by ion selective electrode. Despite this no guideline is, yet, available on the
choice of appropriate TISAB for F- analysis in samples, particularly in presence of other ionic and nonionic species. In this study, the efficacy of ten different TISABs for fluoride estimation in water samples
in presence of F- binding cations, viz. Al3+ and Fe3+ has been investigated. The study suggests that the
TISAB, containing tris - hydroxymethyl aminomethane hydrochloride buffer is probably best suited for F estimation in samples, especially, in presence of high concentrations (1-2 g dm-3) of Al3+.