Re: Converting mg/L to ppm?

To: Aquatic plants list <aquatic-plants at actwin_com>
Subject: Re: Converting mg/L to ppm?
From: Cynthia Powers <cyn at metronet_com>
Date: Sat, 20 Jul 1996 14:25:04 -0500 (CDT)

---------- Forwarded message ----------
>From: tmarch at primenet_com (Todd March)
>Date: Fri, 19 Jul 1996 18:58:38 -0700
>
>Can anyone give me the formulas and explanations for converting mg/litre to
>ppm (parts per million)? A few friends have test results in ppm, and we
>would like to exchange information.
 
 OK, it's complicated but here goes:
 
 Assume that the solution you are concerned with is mostly water since "parts 
 per million" concentrations are pretty small.
 
 Also, remember that pure water at standard temperature and pressure weighs 
 one gram per cubic centimeter. 
 
     1 mg     0.001 g     1000 * 0.001g         1 g            
    ------ =  -------   = -----------------  = ---------------         
   1 litre   1000 cu cm   1000 * 1000 cu cm    1 million cu cm
 
     1 g               1 cu cm       1 part
  ---------------  X  ---------  = ------------- = 1 ppm
  1 million cu cm      1 gram      million parts
 
 :-)
 
 George