Praktikum I Zulvana
Praktikum I Zulvana
Praktikum I Zulvana
INORGANIC LABWORK
CARBONATOTETRAAMMINCOBALT(III) COMPLEX ION
BY
Name
Number of student
: 12/327756/PA/14373
Day,Dates
RATIFICATION PAGE
LABWORK REPORT
Zulvana A. Harvian
12/327756/PA/14373
Assistant
Practicant
Benny Wahyudianto
Zuvaana A. Harvian
.
Keyword: karbonatotetraaminkobalt (III) ion complex
I.)
II.)
THEORITICAL BACKGROUND
A complex ion can be defined as an ion composed of the
central atom binding coordination number of ions or neutral
molecules. Ions or neutral molecules as species bound to the
central atom in a complex ion is usually called ligands. This
species has one or more pairs of free electrons and acts as an
electron-pair donor in the formation of coordination bonds.
In this experiment, the complex ion [Co(NH3)4CO3]+ will
be made from the original compound cobalt salt, Co(NO3)2.6H2O.
If the salt is dissolved in water aka tone in the form of a complex
ion [Co(H2O)6]2+ and NO3- ions. In principle, the manufacture of
the complex ion involves the replacement of the ligand NH3 and
H2O ligand followed by oxidation of the central atom of Co3+. In
the execution of the manufacture of complex ion [Co (NH3) 4CO3]
+ is carried out by reacting Co(NO3)2.6H2O , NH4OH and NH4CO3
in water medium and followed oxidation with H2O2.
A compound [Co(NH3)4CO3]NO3 is crystal somewhat
soluble in water, then recrystallization can not be used in refining
the results of this experiment. Further characterization of the
resulting compounds will be dissolved by studying the behavior of
the electrical conductivity of the solution of the resulting
compound.
III.)
EXPERIMENTAL DESIGN
i.)
IV.)
Table of Result
Name
Weight
I heart U
1.86 g
I need U
1.91 g
Discussions
Compound or complex ion composed of the central ion, which
is generally a metal ion or atom, and a number of ligands.
Covalently bound ligand coordination, with metal or ion center.
The amount of bound ligand is determined by the coordination
number and type of ligands. Co2+ metal ions have oxidation
number 6, which means it can receive six pairs of electron
donor. Oxidation by H2O2 . The reaction occurred :
H2O2+[Co(NH3)6]2++CO3 [Co(NH3)4CO3]+
This experiment aimed to learn how to prepration, purification,
and characterization of complex [Co(NH3)4CO3]+. Created a
complex of [Co(H2O)6]2+ it used 1.5 g of crystalline
Co(NO3)2.6H2O diluted with 3 mL of distilled water in a glass
beaker. Dissolution function for the reaction can be run with
the maximum. In addition, by dissolving salt crystals will break
down into ions and ion complexes of [Co(NH3)4CO3]2+ and
NO3- ion.
While (NH4)2CO3 dissolved as much as 2 g to 6 mL of distilled
water and added 6 ml of concentrated NH4OH. The second
solution is then mixed and heated while stirring continuously
then added cobalt. Heating aimed to increase the speed of the
reaction by adding heat energy or heat. With the heat or energy
will at enhancing energy collisions between molecules. Stirring
will increase the intensity of contact and collision between
molecules. Heating is carried out until the solution becomes 510 mL. Heating is done in a hood because in this reaction
produced gas or ammonia NH3. Heating must be maintained so
that the solution does not boil. When heated is added 30% of
H2O2 as an oxidant of Co2+.
Ligands in the complex ion will be replaced with NH3 for H2O
is a ligand which is weaker than with NH3. In the case of
cobalt, however, only four of the six H2O molecule ligands that
can be replaced by NH3 and forming a red solution. H2O two
ligands that are not replaced with NH3 is then replaced /
pressured by the ligand molecule CO32Color came from the ion complex formed. D orbitals in cobalt
(II) will undergo splitting the H2O ligand binding. electrons can
undergo a transition from the orbital t2g towards orbital eg by
absorbing wavelengths in the visible light spectra. Colors were
not absorbed (complementary colors) will appear as the color of
complex ompounds. Once the volume 5-10 mL solution was
filtered with filter paper and poured into a glass beaker and then
cooled in a cooler / refrigerator to form a crystalline precipitate.
If a precipitate has formed, the solution is filtered with
Whatman 42 paper and Buchner filter until the water content of
truly - really little. Later precipitate was washed with ethanol
and water bertetes - drops. , washing with water intended for
mengihilangkan ions - ions that are still attached to the crystals,
while ethanol is used to eliminate pengotor.kristal oven-dried.
The crystals were formed weighed.
Crystals are formed deep purple with a weight of 1.86 g. weight
yield is 38.25% .The yield obtained relatively low this can be
due to several things. Unreacted reactants maximum, so that the
complex compounds formed only slightly. Can also occur
because the water content in the solution is still quite high,
CONCLUSIONS
The conclusion that can be derived from these experiments is a
complex compound [Co(NH4)4CO3]NO3- shaped purple crystals. In
aqueous solution, the complex [Co(NH4)4CO3]NO3- form two ions are
complex ion complex [Co(NH4)4CO3]+ and NO3. The yield of the
practicant group was 38.25%. with mass 1.86 grams while other
groups have yield 39.63% with the masses 1.91 grams
VI.)
REFERENCES
Lawrance, Geoffrey A. , 2010, Introduction to Coordination
Chemistry, John Wiley&Sons, United Kingdom
Svehla, G. ,1979, Vogels Textbook of Macro and Semimicro
Qualitative Inorganic Analysis, Longman, New York
CALCULATION
mol Co(NO3).6H2O = 0.026 mol
mol (NH4)2CO3 = 0.105 mol
mol NH3 = 0.42 mol
Pers. reaksi :
Co(H2O)6
6H2O (l)
2+
Mula
0.026 mol
0.42 mol
0.105 mol
Reaksi
0.026 mol
0.026 mol
0.026 mol
Sisa
0.026 mol
0.026 mol