What element has two electrons in its 4d sub level?

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.

Which scientists contributed to the determination of how cfcs in clouds in the upper atmosphere could destroy ozone molecules

If there are 3.5 moles of koh, how many moles of naoh can be produced? question 1 options: a)3.0 moles naoh b)3.5 moles naoh c)1 moles naoh d)9 moles naoh