Let’s implement the solution:
In accordance with the condition of the task, we write the data:
Xr -? m = 14.2 g
MnO2 + 4HCl = Cl2 + MnCl2 + 2H2O – OBP, chlorine is evolved;
M (MnO2) = 86.9 g / mol;
M (Cl2) = 71 g / mol;
Y (Cl2) = m / M = 14.2 / 71 = 0.2 mol;
Y (MnO2) = 0.2 mol since the amount of substances is 1 mol.
We find the mass of the original substance:
m (MnO2) = Y * M = 0.2 * 86.9 = 17.38 g
Answer: the mass of manganese oxide is 17.38 g
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