Question

Write an essay of the required length explaining how to prepare exactly 50 mL of an aqueous solution of NaCl that has a concentration of 12.0 ppm and an inherent error (precision) of 1% or less. Include in your essay the reasons for your choice of sample size and equipment at each step.

I just need to know the procedure on how to prepare the solution.. I asked earlier and they gave me 0.6mg which gives me 12ppm but it gave me a huge inherent error %. please help

Answer 1

ppm =   1 g        =      1 g      =       1 mg       =    1 mg     =   1 microgram
            10⁶ mL        1000 L             1 L               1 kg                    1 g

ppm concentration = 1 mg/1L
                                         

12.0 ppm = x mg / 0.05 L

x mg = 12.0 * 0.05

          = 0.6 mg