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

Unit cell, how can i make best assignment on unit cell topic?

how can i make best assignment on unit cell topic?

The electronic configuration of element with atomic number, The electronic ...

The electronic configuration of element with atomic number 24 is : (1) 1s 2 2s 2 2p 6 3s 2 3p 6 3d 4 4s 2       (2) 1s 2 2s 2 2p 6 3s 2 3p 6 3d 10         (3)

Formox, what is formox what does it do and is it good or bad for environmen...

what is formox what does it do and is it good or bad for environment

The gas constant of the ideal gas, A piston device haves 0.8 kg of an ideal...

A piston device haves 0.8 kg of an ideal gas initially at 200 kPa and 30oC. The gas is then compressed slowly in a polytropic process during which PV1.3 = constant until the volume

What are changes in matter, Q. What are Changes in Matter? Matter is ab...

Q. What are Changes in Matter? Matter is able to undergo two fundamental kinds of changes. Changes that don't alter the composition of matter are called physical changes. Sta

Making Copper Sulphate Crystals, I would like to know why you stop heating ...

I would like to know why you stop heating the sulphuric acid before placing in the copper oxide in making copper sulphate crystals

Basic organic chemistry, can you locate ortho,meta para positions on a benz...

can you locate ortho,meta para positions on a benzene ring

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