Decomposition of a 97.1*g mass of potassium chlorate, KClO_3, yields what mass of dioxygen?

1 Answer
Oct 7, 2016

We need a stoichiometrically balanced equaition. Approximately #62.4" g" of dioxygen gas is produced.

Explanation:

We start with a stoichiometrically balanced equation:

KClO_3(s) + Delta rarr KCl(s) + 3/2O_2(g)uarr

To work well, this decompostion reaction requires a small quantity of MnO_2 to act as a catalyst. The stoichiometry is the same.

"Moles of KCl" = (97.1*g)/(74.55*g*mol^-1) = 1.30*mol

Given the stoichiometry, 3/2 equiv of dioxygen are evolved per equiv potassium chlorate.

And thus mass of O_2 = 3/2xx1.30*molxx32.00*g*mol^-1 ~= 62.4*g dioxygen gas.