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

Electrochestry, migration of ions,relatuve speed of ions,,,,,,,,,,,,,,,,,,,...

migration of ions,relatuve speed of ions,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

Explain four applications of adsorption, a. How can a colloidal solution an...

a. How can a colloidal solution and true solution of the similar colour be distinguished from each other? b. Give four applications of adsorption

De?ne surveying, (a) De?ne surveying. Brie?y describe about chain and acces...

(a) De?ne surveying. Brie?y describe about chain and accessories. (b) Sketch the plan and suitable section of a single room having 5.0 m X 4m size and 3m height. Assume the ba

The total magnetic quantum numbers for d-orbital is given, The total magnet...

The total magnetic quantum numbers for d-orbital is given by: (1) 2        (2) 0, ± 1, ± 2      (3) 0, 1, 2           (4) 5 ans:  5

Glucose, Why can''t glucose exist as a gas? What properties make this so?

Why can''t glucose exist as a gas? What properties make this so?

Ionic bonds are usually formed by combination of elements, Ionic bonds are ...

Ionic bonds are usually formed by combination of elements with: (1) High ionisation potential and low electron affinity (2) Low ionisation potential and high electron affini

Describe about the ferromagnetic materials, Describe about the Ferromagneti...

Describe about the Ferromagnetic materials Ferromagnetic materials are those for which k susceptibility is large and positive. These are strongly attracted by magnetic field. I

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