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Urgent Help Me The Fuck Out: Calculations and other shit (1 Viewer)

Legal Hustle

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Aight I need help ASAP....

I dunno how to do thse part per million questions, so it'll be ill if someone can tell me

  1. Oyster were collected from an estuary and tissue samles were weighed. The heavy metals were extracted from 10g of the tissue using conc Nitric acid. The extract was then diluted X 10 and using AAS the diluted sample was found to have a mecure concntent of 0.00032mg.
a) Determine the conc of mercury in ppm in the oyster tissue?

2. In 1950's in Toama(japon) 100 people died fo Ita Itai disaes. Their bones had shrunk and become distoreted...etc.etc. In 1961, 0.68ug of cadmiun was found per gram of rice and cadmiun levels in soils exceeded 3ppm.

a)Why are current levels of cadmium in potable water set at zero and in wastewater at 10ppm

c)Cadmiun pollution is often associated with zinc mining. Why is it so dangerous?
[is it cuz it can cause Itai Itai?]


d)Calcualte the levels of cadmiun in Japanese Rice (ppm)
And Finally

The Hardness of the supplied water was 300ppm. Explain how the student could convert this water into a sample that would be classifed as soft.
 

minijumbuk

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I'm not 100% sure this is right, but I'm pretty confident

1. Dilution of extract = 3.2x10-7g
Undiluted solution of extract should remain unchanged, because the mass of mercury does not change as you add water
So, the undiluted extract is also 3.2x10-7g
Then, the concentration of mercury is 3.2x10-7g / 10 g
But they ask for ppm, so:
Concentration = 3.2x10-7 x 106 g/ 10 g
= 3.2 x 10-8 x 106 / 1g
= 0.032 ppm

2. a)Don't know, haven't done module 3
b)^^^
c)0.68ug = 0.68x10-6g
Therefore concentration in ppm = 0.68x10-6 x 106 / 1 g
= 0.68 ppm
 
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Legal Hustle

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so basically u are make everything into grams over a million....


and for that question one i think u have to times it by ten cuz the next question says 0.5ppm is the amount of mercury usually found,state whether these oysters are safe for eating... but i dunno man.
 

minijumbuk

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I don't know, but I'm sure my working shows a logical pattern. Correct me if I'm wrong though =P
 

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