Converting 26.62 NOx µg/L into mM (millimolars)?

I have to convert a whole lot of nutrient data : $\ce{NH\_4}$, $\ce{PO\_4}$ and $\ce{NO\_x}$ data that is in µg/L into mM (millimolars). 


Could someone give me an example for 26.62 $\ce{NO\_x}$ µg/L? or 7.73 $\ce{PO\_4}$ µg/L? or 14.39 $\ce{NH\_4}$ µg/L?


I have a large data set in Excel to convert and send to someone and want to get it right. Any help would be really appreciated.




I would make it easy for yourself and convert your µg/L to g/L. You can then divide it by the formula weight to obtain the molarity (in M). After this it is just a simple conversion to mM.


I suppose in Excel you can create a new column and use a formula something like this:


=((CELL/106)/Formula weight)\*1000


So for your example of phosphate:


=((0.00000773)/94.97)\*1000


=0.00008139 mM // 8.139x10-5 mM


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