In the mineral beryl left square brackets B e A l subscript 2 end subscript open parentheses S i O subscript 3 end subscript close parentheses subscript 6end subscript right square brackets, what is the ratio of beryllium to aluminum to silicate open parentheses S i O subscript 3 end subscript close parentheses?

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.