A Mixture of KCl and KClO₃ Weighing 1

Multiple Choice

A mixture of KCl and KClO₃ weighing 1.80 g was heated; the dry O₂ generated occupied 1.40  10² mL at STP. What percent of the original mixture was KClO₃? KClO₃ decomposes as follows: 2KClO₃(s)  2KCl(s) + 3O₂(g)

A) 37.2%
B) 72.6%
C) 42.6%
D) 63.8%
E) 28.4%