Atomic absorption spectroscopy, Chemistry

Assignment Help:

Q1: The complexes of Fe+2  with 1, 10- phenanthroline has a molar absorptivity of about 11,000 L/mol cm in water at 510 nm. A 20 ml water sample thought to contain Fe+2  is mixed with an excess of 1,10- phenanthroline. Acetic acid, sodium acetate, and hydroxylamine are also added to buffer the solution and assure that all the iron is reduced to Fe(II). This mixture is diluted with distilled water to a total volume of 50 ml , and the final solution is found to give an absorbance of 0.762 at 510 nm when using a 1 cm cuvette.

a. If it is assumed that there are no absorbing species in this solution other than the Fe+2complex with 1, 10- phenanthroline, what was the concentration of Fe+2

In the original sample?

b. Discuss how the prescence of other species that also absorb at 510 nm would have affected the accuracy of this measurement. Would a positive error or negative error be obtained?

Q2; Copper can be measured by both atomic emission and absorption spectroscopy .

a.    In a copper measurement that is made by atomic emission spectroscopy, a blank solution that is measured intensity at 216.6 nm of 0.2 unit. A 1 ppm Cu+2 solution that is measured under the same conditions gives an emission intensity of 18.4 units and unknown sample produces an emission intensity of 12.7 units. What is the concentration of copper in the sample?

b. Copper measurement is made by atomic absorption spectroscopy of the     same sample and standard. The same blank solution gives an absorbance reading 0.004 units at 216.6 nm and the 1 ppm Cu+2standard has absorbance of 0.305. What do you predict will be absorbance the unknown solution?


Related Discussions:- Atomic absorption spectroscopy

Experimental research, how to write research design in experimental researc...

how to write research design in experimental research

Oleic Acid in Olive Oil, What is the concentration of Oleic Acid in mg/100m...

What is the concentration of Oleic Acid in mg/100ml (Wt/Vol) in Extra Virgin Olive Oil (EVOO)?

Naming, What does this mean? H+/H2O

What does this mean? H+/H2O

Explain cohesive energy, 'Cohesive energy' : In a chemical bond, it is the...

'Cohesive energy' : In a chemical bond, it is the energy needed to dissociate a solid into isolated atoms or molecules as appropriate.

Atoms and molecules, which postulate of daltons theory can explain the law ...

which postulate of daltons theory can explain the law of definite proportions

Lanthanides & acinides, 1. why YbS and YbI2 are semiconducting solids but L...

1. why YbS and YbI2 are semiconducting solids but LaS and LaI2 show metallic character. 2. Why is aqueous solution of Eu2+ thermodynamically less susceptible to oxidation than any

Partition coefficient of acetic acid between octanol and h2o, compare your ...

compare your partition coefficient of acetic acid with the literature and calculate percentage error

Solve, the nitride ion in lithium nitride is composed of 7 protons + 10 ele...

the nitride ion in lithium nitride is composed of 7 protons + 10 electrons. how?

Project, preparation of soyabin milk

preparation of soyabin milk

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd