Potassium perchlorate :
Potassium perchlorate, chemical formula KClO4, is a strong oxidizer. It is a colorless, crystalline substance that melts at about 610 °C. It is one of the most common oxidizers used in fireworks, ammunition percussion caps, explosive primers, and is used variously in propellants, flash compositions, stars, and sparklers. It has been used as a solid rocket propellant, though in that application it has mostly been replaced by the higher performance ammonium perchlorate. KClO4 has the lowest solubility of all perchlorates (2.08 g KClO4 in 100 g H2O at 25 deg C).
It has a molar mass of 138.55 g/mol.
Potassium chlorate :
Potassium chlorate is a compound containing potassium, chlorine and oxygen, with the chemical formula K[ClO3]. In pure form, it is a white crystalline substance. It is the most common chlorate in industrial use, and is usually present in well-stocked laboratories. It is used:
as an oxidizing agent,
to prepare oxygen,
as a disinfectant, especially in bleach,
in safety matches, and
in explosives and fireworks.