Barium sulfate groups that are sensitive to overreduction. With a low surface area, the contact time of the substrate with the catalyst is shorter and thus selectivity is achieved. Palladium on barium sulfate is also used as a catalyst in the Rosenmund reduction. As barium compounds emit a green light when burned, barium salts are often used in green pyrotechnic formulas, but the nitrate and chlorate salts are more common. Barium sulfate is commonly used as a component of "strobe" pyrotechnic compositions. As barium sulfate has high burning point and is insoluble in water, it is used as a coating material in
Potassium chlorate conclave. Potassium chlorate is often used in high school and college laboratories to generate oxygen gas. It is a far cheaper source than a pressurized or cryogenic oxygen tank. Potassium chlorate readily decomposes if heated while in contact with a catalyst, typically manganese(IV) dioxide (MnO). Thus, it may be simply placed in a test tube and heated over a burner. If the test tube is equipped with a one-holed stopper and hose, warm oxygen can be drawn off. The reaction is as follows: Heating it in the absence of a catalyst converts it into potassium perchlorate: With further heating, potassium