Question

In a lab experiment, 5.2 g of Mg reacts with sulfur to form 12.1 g of magnesium sulfide. How much magnesium sulfide would be formed if 5.2 g of Mg were reacted with 13.8 g of S?

How many g?

Answer 1

Mg + S ---------> MgS

first calculate limiting reagent

according to balanced reaction

24.3 g Mg reacts with 32 g S

5.2 g mg reacts with 5.2 x 32 / 24.3 = 6.85 g S

but we hvae 13.8 g S

so Mg is limiting reagent

now

24.3 g Mg gives 56.38 g MgS

5.2 g Mg gives 5.2 x 56.38 / 24.3 = 12.06 g MgS

mass of MgS formed = 12.06 g