Exam (elaborations)

Coordination Complexes - Geometrical Isomerism in Octahedral Complexes University of Calgary CHEM 333

8 views 0 purchase

Course
CHE 423

Institution
CHE 423

Coordination Complexes - Geometrical Isomerism in Octahedral Complexes Anusha Ambaselkar Lab B05 A-1 Feb 11 2021 Abstract: In this experiment, Dichlorobis(ethylenediamine)cobalt(III) Chloride was synthesized in two forms. The trans isomer was made by mixing cobalt chloride hexahydrate, diamin...

[Show more]

Preview 2 out of 7 pages

View example

Uploaded on February 6, 2023
Number of pages 7
Written in 2022/2023
Type Exam (elaborations)
Contains Questions & answers

coordination complexes geometrical isomerism in octahedral complexes
coordination complexes geometrical isomerism in octahedral complexes anusha ambaselkar lab b05 a 1 feb 11 2021 abstract in thi

ExamsConnoisseur

Member since 1 year 429 documents sold

CA$11.47

Added

Add to cart

Add to wishlist

100% satisfaction guarantee
Immediately available after payment
Both online and in PDF
No strings attached

Anusha Ambaselkar

Coordination Complexes - Geometrical Isomerism in Octahedral
Complexes
Anusha Ambaselkar Lab B05 A-1
Feb 11 2021

Abstract:

In this experiment, Dichlorobis(ethylenediamine)cobalt(III) Chloride was synthesized in

two forms. The trans isomer was made by mixing cobalt chloride hexahydrate, diaminoethane,

water and hydrochloric acid and then evaporated and filtered to get a solid product. This product

was heated in an oven to remove the hydrochloric acid which made the final

trans-[Co(en)2Cl2]Cl (1.455g, 60.3%). A portion of the trans isomer was evaporated in water to

create cis-[Co(en)2Cl2]Cl solution(6.47%). Both trans (green solution) and cis (purple solution)

isomers were made into diluted solutions in 50mL volumetric flask. A UV-vis spectrophotometer

measured the absorbance and maximum wavelength for both solutions. The molar absorption

coefficient (trans: 30.306 molLcm ) (cis: 31.565 molLcm ) was calculated using the absorbances and

the calculated concentrations for the cis (0.0109M)and trans (0.0108M) isomers. The maximum

wavelengths were compared to the wavelength ranges for the colors absorbed and reflected.

According to the wavelengths from the spectra, the color reflected for the trans (620.1nm)

isomer was green and for this cis (510.0nm) it was red.

Introduction:

Geometric isomerism which is also known as cis and trans isomerism is a form of

stereoisomerism. Cis and trans isomers differ in the position of the ligands for a coordination

complex. For trans molecules, two identical ligands are on the opposite side of the molecules

and for cis, the two ligands are on the same side. For the coordination complexes of

trans-[Co(en)2Cl2 ]Cl
and cis-[Co(en)2 Cl
2]Cl
synthesized in this experiment, the position of the

two Cl ligands determine whether its a trans or cis isomer.

This study source was downloaded by 100000858936669 from CourseHero.com on 02-06-2023 01:21:35 GMT -06:00

https://www.coursehero.com/file/83007473/Geometrical-Isomerismpdf/

, Anusha Ambaselkar

The purpose of this experiment was to explore the differences between cis and

trans-Dichlorobis(ethylenediamine)cobalt(III) Chloride by obtaining an absorption spectra by

using a Ultraviolet visible spectrophotometer. A UV-vis spectrophotometer refers to absorption

spectroscopy where it measures at what wavelength light is absorbed at for the sample.The

maximum wavelengths determined by the spectra for both isomers were compared to the range

of colors reflected and absorbed at different wavelengths to determine if the experiment was a

success. The absorbance was also measured and the concentrations were calculated for both

to determine the molar absorption coefficient using the Beer-Lambert equation[1].

Product Reactions:

4 CoCl2 + 8 en + 4 HCl + O2 → 4 trans-[CoCl2(en)2]Cl + 2 H2O

trans-[CoCl2(en)2]Cl + H2O + heat → cis-[CoCl2(en)2]Cl + H2O

Methods:

Part A: Preparation of trans-[Co(en)2Cl
]Cl
2

Cobalt chloride hexahydrate (8.6mmol, 2g) and distilled water (5.0mL) in a 250mL

beaker was added. Then a mixture of anhydrous 1,2-diaminoethane (1.0mL) and water (3.0mL)

was added into the chloride solution. Finally, 30% hydrogen peroxide (1.0mL) was added

dropwise to this solution. This solution was heated until the effervescence had stopped (5min)

and after, concentrated hydrochloric acid (5.0mL) was added. The solution was gently

evaporated for another 30min until a dark green thick layer was formed. The beaker was then

placed in an ice water bath (10min). Vacuum filtration was used to filter off the crystals and

washed with 3 small portions of 95% ethanol. Then the powder was placed in an oven (10 min)

to remove the HCl and leave the trans-[Co(en)2Cl
]Cl
2 roduct by itself. This product was a dark
p

green powder.

This study source was downloaded by 100000858936669 from CourseHero.com on 02-06-2023 01:21:35 GMT -06:00

https://www.coursehero.com/file/83007473/Geometrical-Isomerismpdf/

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller ExamsConnoisseur. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for CA$11.47. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

80461 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 14 years now

Start selling

Exam (elaborations)

Coordination Complexes - Geometrical Isomerism in Octahedral Complexes University of Calgary CHEM 333

Document information

Subjects

Written for

Seller

Reviews received

Content preview