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/sci/ - Science & Math

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3255248 No.3255248 [Reply] [Original]

Can anybody help me convert a reading of 0.3mg/l of nitrate (NO−3 and a molecular mass of 62.0049 g/mol) in water into ppm?
Pic related. I need to know the ppm nitrates in an aquarium but can only get the answer in mg/l

>> No.3255299
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3255299

I'm sorry.Is my post not trolly enough?

>> No.3255309

Be useful to know how much water it's in OP.

>> No.3255315

>>3255309
>mg / l

>>3255248
mass fraction or mole fraction?
http://en.wikipedia.org/wiki/Parts-per_notation#Mass_fraction_vs_mole_fraction

In short; for mass fraction: 3mg/(mass of 1 l of water); for mole fraction: (# moles of nitrate in 0.3mg)/(# moles of water in mass of 1 l of water)

>> No.3255318
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3255318

>>3255248
0.087 ppm, OP.

http://www.wolframalpha.com/input/?i=how+many+molecules+of+water+in+1+litre%3F
http://www.wolframalpha.com/input/?i=how+many+molecules+of+NO3+in+0.3+mg
(2.91×10^18)/(3.34×10^25)*1000000

>> No.3255321

>>3255315

Oops. apologies. That'll teach me to read the damn question.