If the were 400 g sample of pond water and it has a concentration of 3.5 ppm dissolved nitrates.
what is the mass of dissolved nitrates in this sample?
note: converting atmospheric pollutant concentrations from ppmv to mg/m3 the conversion factor depends on the temperature at which you want the conversion (usually about 20 to 25 degrees centigrade). at an ambient pressure of 1 atmosphere, the general equation is: mg/m3 = (ppmv)(12.187)(mw) / (273.15 + °c) where: mg/m3= milligrams of gaseous pollutant per cubic meter of ambient air, ppmv= ppm by volume (i. e., volume of gaseous pollutant per 106 volumes of ambient air), mw= molecular weight of the gaseous pollutant, and °c= ambient air temperature in degrees centigrade