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Stuck on this question

Determine the phosphurous content of a 70kg man if it is know than the human body contains 6.3x10^3ppm phosphorous

any ideas, thanks

anyone

70 / 1000000 = 7x10^-5
(7x10^-5) x (6.3x10^3) = 0.441 kg or 441 grams ...i think :K:

...you divide 70 into a million parts and then 6.3x10^3 of those parts are occupied by phosphorus..

i hope you get more replies though, cos i'm not completely sure..

Reply 3

Soloman

Original post by memomemootoo

70 / 1000000 = 7x10^-5
(7x10^-5) x (6.3x10^3) = 0.441 kg or 441 grams ...i think :K:

...you divide 70 into a million parts and then 6.3x10^3 of those parts are occupied by phosphorus..

i hope you get more replies though, cos i'm not completely sure..

ah i was thinking the other way, was gonna turn 6300ppm into kg, once uve found the weight of the phosphorus put it over the 70kg but im struggling to turn ppm into some sort of weight

Reply 4

memomemootoo

Original post by Soloman

ah i was thinking the other way, was gonna turn 6300ppm into kg, once uve found the weight of the phosphorus put it over the 70kg but im struggling to turn ppm into some sort of weight

yeah, i don't think you can turn ppm straight into kg :no:

...because it's all in proportions

..think of it as how you would do a percentage:
eg ~find amount of water in a 50kg man if his water content is 20% (same as 20 parts per hundred)~
..so you divide 50 by 100 and then multiply by 20 to get the mass of water

so in the same way you divide 70 by 1 million and then multiply by 6300