Chapter 5, Problem 5.117QP

Liquid oxygen was first prepared by heating potassium chlorate, KClO_3, in a closed vessel to obtain oxygen at high pressure. The oxygen was cooled until it liquefied.

$2{\text{KClO}}_3(s)\to 2\text{KCl}(s)+3{\text{O}}_2(g)$

If 171 g of potassium chlorate reacts in a 2.70-L vessel, which was initially evacuated, what pressure of oxygen will be attained when the temperature is finally cooled to 25°C? Use the preceding chemical equation and ignore the volume of solid product.