How many protons are there in the neutral atom of 35(superscript)17(subscript)cl? a. 17 b. 19 c. 20 4. 35 5. 37 it would be great if you could tell me why, cause i really don't understand. you!

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.