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Standard sample size

by higherme
Tags: sample, size, standard
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higherme
#1
Sep30-07, 08:25 PM
P: 129
Sometimes, when repeated assays are to be performed, the sample size is standardized and chosen such that the ultimately measured quantigy is numerically equivalent to some other desired proportionate quantity.

suppose the sulfur content of a mineral sample is determined by complete conversion to Ag2S(s) what mass of sample must be chosen so that the number of grams of Ag2S obtained is equal to 4 times the percent sulfur in the sample??


i don't know where do start................
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Gokul43201
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Sep30-07, 10:10 PM
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Begin here: Let the sample contain x% of sulfur (S) and have a mass m. Then the mass of S in the sample is ...
higherme
#3
Sep30-07, 10:17 PM
P: 129
how do i find mass if i don't know how much Ag2S i have?

Gokul43201
#4
Oct1-07, 12:28 AM
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Standard sample size

Assume the mass is "m" and write down an expression for the mass of S in terms of x and m.


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