atomic absorption troublshouting, Chemistry

Assignment Help:
Dear sir,
We need your consultancy in a technical problem that we are confronting, and we would really appreciate your help
We are in the process of implementing the heavy metal analysis in fish and water by atomic atomic absorption spectroscopy,
I’m still in the sample preparation optimization phase, and I’m confronting some problems,

Il explain in brief the problem in my last results obtained:
For arsenic analysis, 0.2 g sample is digested with Nitric acid At 90?C for 45 min ,then placed in oven for 2 hours at 130 ?C, then diluted to desired volume

1- 0.2 g Unknown fish sample spiked with (2.5ml) 1000ppb arsenic standard, after dilution in 25 ml H2O,the theoretical value must be 100 ppb, but the practical value came out 75 ppb
2- 0.2 g Fish muscle certified reference material ,containing 12.7 mg/kg of arsenic, and since the dilution is in 50 ml, then the theoretical value must be 50.8 ppb, the practical value came out 0.57ppb

Knowing that both samples were treated in the same condition and in the same time, the difference in the end results is very weird, please advise concerning any note that can improve our work,
or detect any mistake has been made,
waiting for your reply,many thanks in advance

Related Discussions:- atomic absorption troublshouting

Thermodynamics, Calculate the free energy change of following reaction at29...

Calculate the free energy change of following reaction at298 kelvin H2+I2=2HI if the enthalpy change is 51.8816kj and the entropy change is 166.15j is this reaction thermodyanamica

Methane emissions from landfills, From the EPA the current generation of m...

From the EPA the current generation of methane from landfills in the USA is 12.7 MM tons per year (2009). a. Using the Global Warming Potential of the methane at 20 years, 100

Biocomposite, what are the strong and biodegradable binder?

what are the strong and biodegradable binder?

Why does methyl ethanoate not give iodoform test?, Why does methyl ethanoat...

Why does methyl ethanoate not give iodoform test while ethyl ethanoate does? Ans) Iodoform test for esters is the test given by its products on hydrolysis methyl ethanoate give

Solvent extraction, what is the principle of solvent extraction?

what is the principle of solvent extraction?

Types of substituents which produce directive effect, Types of Substituents...

Types of Substituents which Produce Directive Effect There are two kinds of substituents which generate directive effect are, (i) Those that direct the incoming group to ort

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