A solid oxidizer used in a demonstration is believed to be potassium chlorate (KClO3)…
CHEMISTRY · Multi-part · A Level · Chemistry · Amount of substance · Amount of substance
Problem
A solid oxidizer used in a demonstration is believed to be potassium chlorate (KClO3) mixed with an inert filler. To test its composition, a student heats 5.50 g of the material in a sealed apparatus that directs all gaseous products through a drying tube into a gas-collection bottle. After the reaction goes to completion, 1.24 L of dry oxygen gas is measured at 298 K and 1.00 atm.
(a) Calculate the amount (in moles) of oxygen gas collected under the stated conditions.
(b) Determine the mass of pure potassium chlorate that decomposed to produce the measured oxygen.
(c) Compute the percent purity of potassium chlorate in the original solid oxidizer.
(d) Describe one experimental modification that would allow the student to verify that no other gaseous products were formed during the thermal decomposition. Explain how the modification would provide that verification.