Roman mixes 12 liters of 8% acid solution with a 20% acid solution, which results in a 16% acid solution. find the number of liters of 20% acid solution in the new mixture. construct a table to organize the information, and show all of your work to solve the problem.

The content of manganese (mn) in steel was determined spectrophotometrically and with the use of the standard addition method. an unknown sample of mn from a digested steel sample gave an absorbance of 0.185 when analyzed spectrophotometrically. when 5.00 ml of solution containing 95.5 ppm mn was added to 50.0 ml of the unknown steel solution (digested sample), the absorbance was 0.248. calculate the concentration, in parts-per-million (ppm), of mn in the digested steel sample solution.