in pictures
What shape is my molecule?
Linear
O
C
O
H
H
S
O
O
How many O
atoms or
groups does the
central atom H
have?
O
…two atoms
or groups
No
Does the central
atom have an
additional lone pair H
of electrons?
2–
Cl
Ni
Cl
C
H
O
H C
H S
O
Cl
Cl
Cl
Yes
C
Bent
O
Cl
Co
Cl
H
H
O
O
Pd
Cl
2–
S O
O
…four atoms
or groups
Cl
Cl
O
C
O
C
NC
O
Ni
C
O
S
O
Cl
Ni
Cl O
Cl
S
O
Cl
H
H
C
H
H
2–
Download this poster at Cl
www.hoddereducation.co.uk/chemistryreviewextras
Ni
2–
Cl
Cl
Cl
Cl
Co
Cl
Cl
Cl
H
H O
H
H
O
S
O NC O
NC
Ni
2– H
C
Co H
Cl
2– Cl H
Cl
O
Pd
Cl
H
H
H C
Cl NC 2–
Cl
NC
CN
Fe
CN
C
S
2–
H
Ni
Cl O
Cl
NC
S 2–
O
B
Co
Cl
CN
NC F
F
NC
Cl
Cl
F
C CN
Ni
CN
N Cl
Cl
H Cl
Cl
N
O
NC
NC
O
H
H
O
CN
2–
H
Cl Pd
F
Cl
2–
Cl
No
Cl
O 2–
C
Fe
Cl 2–
CN 2+
Cl Pd
Cl Cl 2–
CN
Cl Pd
Cl
Cl
B
F
C 2–
H
H O
H O
O O
H
N
C
CN
CN
Square planar
H O
H
F
CN 2+
Ni B F
F
CN F
B
F
F
O 2–
C
N
H
H
O
Trigonal planar F
O
C
O
2–
O
F
O
N
H
C H
H
H
N
H O H C
H S
F
B
O 2–
O
Cl F Pd
Cl
O 2–
Cl
O
Cl
CN
NC
CN
B Fe
F NC F
CN
CN
2–
O 2–
C
O
S
2–
O
O F
O C
B
F
O 2–
O
Trigonal pyramidal
N
C
NC
H
O
H NC
CN 2+
2–
Ni
O
O
NC
2– CN N H
S
H
O
H
O
O
NC
N
H
2–
H Cl
S
H
Cl
O
NC
O
CN
O
3+
NH 3
2–
CN S
H 3 N
NH 3
O
O N
Co
O
C
H 3 N
NH 3
N
NH 3
C
O
F
2–
Yes
S
NC
Fe
H
N
CN
H
H
CN S
O
O
O
2–
C
N
Cl
Cl
N
2–
Cl
CN
H
Fe O 2– Cl
C
NC
CN
H CN 2+ O NC
Co
N
C Cl Pd CN Cl
H
Ni
Fe
Cl
C
O CN
2–
CN 2+
NC NC C CN Cl
Cl
CN
2–
Ni H
Cl H
CN
F F –
H Cl Pd CN Cl
CN
NC
NC
CN
Fe
H
2– NH
3+
NC
CN
Co C Cl
2+
Cl
F F –
NC
CN Fe
CN
F P F NC
Cl
CN
2– 3
Fe
NC
Cl
H
Ni NC NC
NH 3
Cl H 3 N
H
CN
Co
CN
F F
H
F N
P H F
CN
NC
Co
Fe
CN
Cl
H NC H
Ni ClCl
2+
2–
NC
Cl
CN
H 3 N Cl
NH 3
NC
CN
Cl Cl 2– 2–
Cl
F F
CN C
CN
Ni
Cl NH present)
CN
3
on the species
Cl (depending
Pd
N NC Fe
Cl
CN CN
NC
Co CN
NC
N
C
CN
2–
Ni
S
Cl
2–
Fe
Cl
Cl
Cl
C
O
N
Cl Cl
Cl
O
NC
CN
NC
NC
Fe CN CN
Cl
O
NC
CN
CN
Co
N
Cl
NC C
CN
Fe
Cl
Cl
NC
NC
CN 2+
C
CN
CN Dux assists with inorganic research in the Department of Chemistry
NC
Emma
Fe
Ni
CN
3+
N
NH 3
F F –
at the University of York and is a sub-editor for C hemistry R eview
CN
C CN
NC
NC
3+
H 3 N
NH 3
NH 3
N
F F –
CN
F P F NC
Fe
Co
CN
H 3 N
NH 3
H 3 N
NH N
NC
CN
3
F P F
Co
F F
NC
C
NH 3
Fe
C
NH 3
N H 3 N
NC
F F
CN
3+
NH 3
–
NH 3
CN
F F
C
CN NH 3
H 3 N
3+
–
N
NH
3
F P F F F
NC
Fe Co NH CN
H 3 N H 3 N
3 NH 3
F F F P F
NC
NH 3 Co
3+
H 3 N
NH 3
F F –
F NH F 3
NH 3
H 3 N
NH 3
C
F P F
Co
3+
–
NH 3
F NH
N
H 3 N
F 3
F F
H 3 N
NH 3
NH 3
F P F
Co
H 3 N
NH 3
F F
NH 3
Cl
H
O
C
Cl
O Cl
F
O
O
…six atoms
or groups
O
N
H
F
Does the central atom B
F
F
have an additional lone
O 2–
pair of electrons?
O
C
F
O 2–
Cl
CN 2+
CN
NC
2– O
H
H
O
S O C H O
H
Cl
H
O
Cl O
S
O
O C
H
H
H
O
2–
H
H
Cl
Ni
Cl
ChemistryReviewExtras
…three atoms
or groups
F
B
F
O
Tetrahedral
H
O
H
O
O
O
C
O
Cl
Cl
Cl
Cl
Ni
2–
Cl
Cl
Cl
Octahedral
Common Ion Effect on
Completely Soluble Salts
H 3 N
H 3 N
NH 3
Co
NH 3
3+
NH 3
NH 3
F
F
P
F
F
–
F
F
Salts of ions -like NO3-, Na + , K + , NH4 + - that dissolve via
reactions that go to completion are called completely
soluble salts. Generally a substance will dissolve in a
solvent if the intermolecular forces in the solute and
solvent are similar. There are two factors that affect
solubility of a salt: temperature and the presence of
other solutes (Common Ion Effect). On a broad term
the common ion affect involves a solution and solute in
equilibrium (saturated), adding a common ion (an ion
that is found in both the solute and the externally added
salt) decreases the solubility of the salt. (Lumen, n.d.).
The mechanism can be summarized as follows:
References:
Mani, S. and Bharagava, R.N., 2016. Exposure to crystal
violet, its toxic, genotoxic and carcinogenic effects on envi-
ronment and its degradation and detoxification for environ-
mental safety. Reviews of Environmental Contamination and
Toxicology, 237: 71-104.
Saha, P., Chowdhurt, S., Gupta, S. and Kumar, I., (2010). Insi-
ght into adsorption equilibrium, kinetics and thermodynamics
of Malachite Green onto clayey soil of Indian origin. Chemical
Engineering Journal, 165: 874–882.
Singh, H., Chauhan, G., Jain, A.K. and Sharma, S.K., 2017. Ad-
sorptive potential of agricultural wastes for removal of dyes
from aqueous solutions. Journal of Environmental Chemical
Engineering, 5: 122-135.
İdil BÜYÜKGÖLCİGEZLİ
9- D
Figure 1.1: How Common Ion Effect Mechanism Works
In this investigation, completely soluble salts NaCl and KCl
which both have Cl- ions are used. For the common ion
effect, a saturated KCl solution is prepared by dissolving
excess KCl with water. Different amounts of NaCl are
added to the solution and the change in the solubility
of the solution is measured with the conductivity probe.
The experiment was approached with an environmentally
and ethically caring viewpoint as situations threatening
human health and investigations on living organisms
were strongly avoided, as appropriate to the ethical
THE CLAPPER 2018 - 2019
51
to remove these dyes from peripheral water bodies, to
which they are released from textile and press factories
(Mani ve Bharagava, 2016).
Firstly, Pyracantha coccinea fruits were collected from
a local garden and they were cleaned out from non-
experimental parts. The fruits were later washed with
distilled water, dried and ground. Then, the model
solutions of Safranin O and Crystal Violet dyes were
prepared. The absorption peaks of the model solutions
were measured using an Ultraviolet- Visible Region
Biradial Spectrophotometer. These absorption peaks
showed the characteristic wavelengths of the dyes
used and further studies were conducted using those
wavelengths. Then, equal amounts of Pyracantha
coccinea biomass were added to samples from the
model solutions and the mixtures were incubated
at 150 rpm speed and at room temperature. The
samples were then centrifuged and were exposed to
spectrophotometric measurements. The intensity of the
absorption peaks measured are directly proportional
to the concentration of dye in the liquid part of the
sample. Then, the percentage efficiency of the removal
of dyes were calculated using a simple mathematical
formula. The decrease in the absorption peak intensity
can be explained by the decreasing dye concentration,
due to the dye removal by the biosorbent. Hence, it is
possible to say that the dye removal had occurred. The
findings showed that Pyracantha coccinea could be
used as a biosorbent in the removal of Safranin O and
Crystal Violet dyes. 100% of Safranin O and 87.67% of
Crystal Violet were removed by the Pyracantha coccinea
biomass in the first trial and further studies for finding
the optimum circumstances were performed.