Question

PLEASE TYPE

Suppose you had the following information about nitrate (NO3) concentration in three streams:

Stream A -- 3mg/L NaNO3

Stream B -- 3mg/L NO3

Stream C -- ppb NO3

what is the actual nitrogen (N) concentration in each of these three streams in mg/L?

Please Type and Please show all work

Answer 1

Molecular weight of NaNO₃ = 85

Atomic weight of N = 14

so % of N in 1 mol of NaNO₃ = 14/85*100 = 16.4 %

So N mol in

in Stream A Nitrogen concentration = 0.003/85 (mol of nitrogen)* 16.4 % = 3.52 *10^-5* 16.4/100 = 5.78 * 10^-6 mol

concentration of N = 5.78 * 10^-6 * 14 = 8.1 * 10^-5 mg/L

Molecular Wt. of NO3 = 62

so % of N in 1 mol of NO₃ = 14/62*100 = 22.6 %

in Stream B Nitrogen concentration = 0.003/62 (mol of nitrogen)* 22.6 % = 4.838 *10^-5* 22.6/100 = 1.09 * 10^-5 mol

concentration of N = 1.09 * 10^-5 * 14 = 1.5 * 10^-4 mg/L

in stream C nitrogen concentration = 1.09 * 10^-5 mol * 100000000 ppb = 1090 ppb