# Chemical Forums

## Chemistry Forums for Students => Analytical Chemistry Forum => Topic started by: kaahtivak on April 03, 2008, 10:30:13 AM

Title: How do I convert μmol/L into μg/L ?
Post by: kaahtivak on April 03, 2008, 10:30:13 AM
Hi
I really need to knw how do to convert μmol/L  into μg/L ? I have looked everywhere can't find it. If possible give an example.
Thanks
Kav
Title: Re: How do I convert μmol/L into μg/L ?
Post by: Borek on April 03, 2008, 11:20:11 AM
You have to know your substance - you can't convert moles/mass without knowing molar mass. For general conversion ideas google dimensional analysis.
Title: Re: How do I convert μmol/L into μg/L ?
Post by: kaahtivak on April 03, 2008, 02:35:11 PM
Yeah it is the measurement for silicon. Thak You
Title: Re: How do I convert μmol/L into μg/L ?
Post by: JGK on April 03, 2008, 03:44:34 PM
silicon has a molecular weight of 14

a 1 molar solution is 14 g of silicon in 1 litre which is a concentration of  (wt/Volume)
14 g/L = 0.014 g/mL

So 1 M = 0.014g/mL or 14 mg/mL
1 mM = 0.000014 g/mL = 0.014 mg/mL = 14 µg/mL
1 µM =0.00000014 g/mL = 0.000014 µg/mL = 0.014 µg/mL

therefore to convert µM to µg/mL multiply by 0.014

it ain't rocket science
Title: Re: How do I convert μmol/L into μg/L ?
Post by: sjb on April 06, 2008, 06:11:36 AM
silicon has a molecular weight of 14

Wrong, but the calculation principle is right (at least, apart from the second µ in the last line).

See e.g. http://en.wikipedia.org/w/index.php?title=Silicon&oldid=203639537
Title: Re: How do I convert μmol/L into μg/L ?
Post by: JGK on April 07, 2008, 08:10:27 AM
silicon has a molecular weight of 28

a 1 molar solution is 28 g of silicon in 1 litre which is a concentration of  (wt/Volume)
14 g/L = 0.028 g/mL

So 1 M = 0.028 g/mL or 28 mg/mL
1 mM = 0.000028 g/mL = 0.028 mg/mL = 28 µg/mL
1 µM =0.00000028 g/mL = 0.000028 mg/mL = 0.028 µg/mL

therefore to convert µM to µg/mL multiply by 0.028

it ain't rocket science

Corrected, obviusly rocket science was beyond even me when I sent that one out  :o
Title: Re: How do I convert μmol/L into μg/L ?
Post by: Valdorod on April 07, 2008, 12:46:46 PM
Rocket Science

Conversions

MARS CLIMATE ORBITER

120 million dollars waisted because rocket scientists at NASA could not do conversions

:o

Valdo

Title: Re: How do I convert μmol/L into μg/L ?
Post by: The Roseate Spoonbill on April 13, 2008, 11:34:22 PM
μmol/L*(x/μmol) = μg/L

x = the number of grams per micromole. Just check a decnet periodic table. and then multiply by a million.