The mass of manganese obtained by the aluminothermal method from 0.2 mol of MnO2 is

Let’s execute the solution:
According to the condition of the problem, we write down the equation of the process:
3MnO2 + 4Al = 3Mn + 2Al2O3 – OBP, manganese was formed;
Let’s determine the amount of substances:
Y (MnO2) = 0.2 mol;
Y (Mn) = 0.2 mol since the amount of substances is equal to 3 mol.
Find the mass of the metal:
m (Mn) = Y * M = 0.2 * 54.9 = 10.98 g
Answer: the mass of manganese obtained by aluminothermy is 10.98 g