Oxygen Can Be Produced in the Laboratory by the Reaction

Multiple Choice

Oxygen can be produced in the laboratory by the reaction: 2KClO₃(s)  2KCl(s) + 3O₂(g)
How many moles of potassium chlorate are needed to produce 257 mL of oxygen,collected over water at 14C and 97.6 kPa? The vapor pressure of water at 14C is
1.60 kPa.

A) 6.89  10^3
B) 7.00  10^3
C) 7.12  10^3
D) 2.06  10^3
E) 1.55  10^3