Which statement is true? A. Less reactive substances will not undergo chemical reactions.
B. Reactivity is the rate at which a substance undergoes a chemical reaction.
C. A substance's reactivity is determined by its location in the periodic table.
D. Every element in the periodic table reacts strongly with water.

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.