2NiS2(s)+5O2(g)=2NiO(s)+4SO2(g)

Question

1. how many kilograms of NiO would be formed from the reaction of .0125 mol of NiS2?

2. How many grams of O2 are needed to cmpletely react with 3.74 g of NiS2.

Answer 1

Convert 0.0125 mol NiS2 to mols NiO. That is 0.0125 mol NiS2 x (2 mol NiO/2 mol NiS2) = 0.0125 mol NiS2 x 2/2 = 0.0125 mol NiO.
Then g = mols NiO x molar mass NiO= ?

For part b convert g NiS2 to mols, convert that to mols O2 and that to grams O2. Follow the steps from part a.