Chlorine is prepared in the laboratory by treating manganese dioxide (MnO2) with aqueous hydrochloric acid according to the reaction


How many grams of HCl react with 5.0 g of manganese dioxide?

Given:

Mass of Manganese Dioxide = 5 g


Atomic Mass of Manganese = 55g


Atomic Mass of Oxygen = 16g


Atomic Mass of Hydrogen = 1g


Molecular Mass of MnO2 = 55 + [16×2]


= 55 + 32


= 87g


Molecular Mass of HCl = 1 + 35.5


= 36.5g


So by observing the chemical reaction we see that,


1moles of MnO2 reacts with 4moles of HCl


87g of MnO2→ 4×36.5g of HCl


So 5g of MnO2→ X g of HCl


X = [146×5]/87


X = 730/87


X = 8.39g


So, 8.4g of HCl will react completely with 5g of MnO2.


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