Metallic aluminum reacts with mno2 at elevated temperatures to form manganese metal and aluminum oxide. a mixture of the two reactants is 67.2% mole percent al.
find the theoretical yield (in grams) of manganese from the reaction of 290g of this mixture.

What is the lowest number energy level where a d sublevel is found

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.

Who discovered a pattern to the elements in 1869?