J.R. S. answered 11/30/21
Ph.D. University Professor with 10+ years Tutoring Experience
2KMnO4 + 16HCl → 2KCl + 2MnCl2 + 5Cl2 + 8H2O ... balanced equation
If you don't know how to obtain this balanced equation, you can submit another question asking about that.
Since we are given the mass of both reactants, we will have find out which, if either, is limiting. An easy way to do this is to divide the moles of each reactant by its coefficient in the balanced equation, and whichever value is less is the limiting reactant.
For KMnO4: 70.0 g KMnO4 x 1 mol KMnO4 / 158.0 g = 0.4430 mols KMnO4 (÷2 -> 0.2215)
For HCl: 75.0 g HCl x 1 mol HCl / 36.46 g = 2.057 mols HCl (÷16 -> 0.1286)
Since 0.1286 is less than 0.2215, HCl IS LIMITING
Now we use the 2.057 mols HCl to find the amount of Cl2 that can be formed:
2.057 mols HCl x 5 mols Cl2 / 16 mols HCl x 70.91 g Cl2 / mol Cl2 = 45.58 g Cl2 = 45.6 g Cl2 (3 sig.figs.)