identify the range of tests for metal pollution (1 Viewer)

[Steven12]

i know there is the precipitation method
there is AAS

what else?

i need to do the report for chemistry, and i really want to impress the teacher.

I need to explain the range of test to
Identify the heavy metal pollution
Monitor the possible eutrophication of waterways.

And also where are the sources for metal pollution?
any good suggestions?

 

[kimmeh]

i think AAS and precipitating are the main ways to test for the presence of metal ions. The main sources of metal pollution would have to be from our sewage, run off from farming areas, roads, dumps, industrial effluents. I dont see the need to impress, because all you really need is to address the dot point.

 

[CM_Tutor]

AAS is a terrible method for identifying heavy metal pollution. You should do AES to identify the pollution, then AAS to quantify it.

Another technique that could be used would be cation exchange liquid chromatography, which allows for both identification and quantification of cations, but I'm not sure how well it works for simple metal cations - AAS is usual the analysis method of choice.

Some metal cations can also be quantified by gravimmetric analysis. The syllabus covers the gravimmetric analysis of sulfate from fertiliser, and similar methods exist for some cations. Nickel(II) ions, for example, can be gravimmetrically determined by precipitation with dimethylgyoxime.

Afterthought: If you want a local flavour, you could talk about high lead levels in Glebe.

 

[Steven12]

thanks CM

i looked up the cation exchange tomography.
very complicated and its mainly for separaing ions in proteins. so....

So there is only 2 method?

precipitation and AES

so much for "range of tests"

 

[cko]

o i hate this dot point its fkn shyt, last year i had to do as a take home do-it-urself thing n i dint get it so good so i just called up tha HSC helpline n askd for the answer. Well for tha heavy metals one u could do yeh AAS but i don't think that ppt reactions wud help much considering that ur talkn bout trace elements, so u cud try it but u wudnt see much ppts hapning, another thing u could try is colorimetry as a quantitative test

 

[CM_Tutor]

Steven12, you should talk about AES and AAS - both have their strengths. AES is better for identifying a heavy metal pollutant, AAS for quantifying how much is present. My point was that, since you need to use different light sources and standards for AAS, you could spend ages examining a sample and still not figure out what cation is present. So, turn to AES.

You also skipped over gravimmetric determination. This is related to precipitation a bit like AAS is to AES. Precipitation is OK for identification (ie as a qualitative test), but a gravimmetric detemination is better for quantifying.