How much substance and mass of iron is required for the reaction with 16 g of sulfur?

Given:
m (S) = 16 g

Find:
n (Fe) -?
m (Fe) -?

Solution:
1) Write the equation of a chemical reaction:
Fe + S => FeS;
2) Calculate the molar masses of S and Fe:
M (S) = Mr (S) = Ar (S) = 32 g / mol;
M (Fe) = Mr (Fe) = Ar (Fe) = 56 g / mol;
3) Calculate the amount of substance S:
n (S) = m (S) / M (S) = 16/32 = 0.5 mol;
4) Determine the amount of Fe substance:
n (Fe) = n (S) = 0.5 mol;
5) Calculate the mass of Fe:
m (Fe) = n (Fe) * M (Fe) = 0.5 * 56 = 28 g.

Answer: The amount of Fe is 0.5 mol; weight – 28 g.