PLEASE help due in 25 minutes Determine the mass in grams of each of the following:
5.04 x 1024 atoms N

2.01 x 1024 atoms Ca

8.32 x 1021 atoms Sn

Determine the number of particles contained in each of the following:
50.3 g Cu

145g Si

0.67 g Cl

Idon’t know how to solve this question

In the lab, ammonia was mixed with water to form ammonium hydroxide. what is/are the reactant(s)? o water and ammonia o ammonia o ammonium hydroxide need

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.