Use the periodic table to match each of the following element symbols to its name, atomic mass, or atomic number.
match term definition
na a) 20.180 u (atomic mass)
ne b) 7 (atomic number)
n c) sodium

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.