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Question

A 3.8-mol sample of KClO3 was decomposed according to the equation How many moles of O2 are formed assuming 100% yield?

a. 5.7 mol

b. 1.9 mol

c. 3.8 mol

d. 2.5 mol

e. 3.2 mol

Answer 1

First, balance the reaction, then just use the mole ratio: 2 KClO₃ --> 2 KCl + 3 O₂.

(3.8 mol KClO₃) * (3 mol O₂ / 2 mol KClO₃) = 5.7 moles.