Barium chlorate in some sodium contamination, which is undesirable for pyrotechnic purposes, where the strong yellow of sodium can easily overpower the green of barium. Sodium-free barium chlorate can be produced directly through electrolysis: It can also be produced by the reaction of barium carbonate with boiling ammonium chlorate solution: The reaction initially produces barium chlorate and ammonium carbonate; boiling the solution decomposes the ammonium carbonate and drives off the resulting ammonia and carbon dioxide, leaving only barium chlorate in solution. When exposed to heat, barium chlorate alone will decompose to barium chloride and oxygen: Barium chlorate is used to produce chloric
Barium sulfate mixture and make it hard to see the color of the indicator. Barium sulfate added to the mixture binds with these particles, making them heavier so they fall to the bottom, leaving a clearer solution. In colorimetry, barium sulfate is used as a near-perfect diffuser when measuring light sources. In metal casting, the moulds used are often coated with barium sulfate in order to prevent the molten metal from bonding with the mould. It is also used in brake linings, anacoustic foams, powder coatings, and root canal filling. Barium sulfate is used as a catalyst support when selectively hydrogenating functional