Calculation nutrient element concentration sin ppmand mM

Appendix5.1. Calculationof nutrientelement concentrationsin ppmand mM. The calculations below will be demonstrated by the GTA in Lab 6. (A) Informationrequired Molecular mass of elements Ca = 40.08 g/mole; N = 14.01 g/mole; O = 16.00 g/mole; K = 39.10 g/mole; Mg = 24.31 g/mole; S = 32.06 g/mole; H = 1.01 g/mole; P = 30.97 g/mole Concentration of salt stocks and dilution See Table5.1 (B) Sample Calculationfor a HypotheticalStock Solution ContainingK What is the concentration of K provided by KCI if 4 mLs of a 2 M stock was diluted to 1 Liter(L) in mM and ppm For this calculation, the elemental concentration of K is being determined and not the concentration of the salt (KCI) providing the element. In a solution, ppm = mg/L; for this calculation it is mg element. (a) Determine concentration of KCI used in mM. 2 M stock KCI = 2 moles KCI/ 1 L (1000 mL) To make up the dilute K solution, 4 mLs of 2 M KCI was added to a final volume of 1L final diluted solution (2 mole KC1/1000 mLs) = (x mole KC1/4 mLs), x = 8 X 10-3 moles KCl in 1L = 8 mM KCI (b) Determine the concentration of K in mM Since there is only one K per KCl molecule, there is also 8 mM K from KCI. (c) Determine the concentration of K in ppm Since ppm = mg/L, 8 mM K X 39.10 g/mole (Molecular mass)= 313 mg/L = 313 ppm K from KCI.