Current location - Recipe Complete Network - Complete recipe book - Why do cobalt chloride and sodium hydroxide finally turn brown?
Why do cobalt chloride and sodium hydroxide finally turn brown?
Because sodium hydroxide is easily oxidized to brown under alkaline conditions, sodium hydroxide is a white translucent crystalline solid. Its aqueous solution has astringency and satiny.

When sodium hydroxide is dissolved in water, it will be completely dissociated into sodium ions and hydroxide ions, which has the universality of alkali. Cobalt chloride crystal is stable at room temperature, loses crystallization water and turns blue when heated, and turns red in humid air.

When heated or added with concentrated hydrochloric acid, chloride or organic solvent, its aqueous solution will turn blue. Crystallization at 30 ~ 45℃, weathering and turbidity, heating at 45 ~ 50℃ for 4 hours to be tetrahydrate, and heating to 1 10℃ to be anhydrous.

Expand the use of cobalt chloride

Used in instrument manufacturing, producing barometer, hydrometer, dry and wet indicator, etc. Ceramic industry is used as colorant. Paint industry is used to make paint drier. Used to prepare compound feed in animal husbandry. The brewing industry is used as a stabilizer for beer foam. The defense industry is used to make gas masks. Used as a catalyst in chemical reactions.

In analytical chemistry, it is used for spot analysis of zinc, haploid breeding, in addition, it is also used to make hidden ink, cobalt chloride test paper, color-changing silica gel and so on. It is also used as an absorbent for ammonia.

Baidu encyclopedia-cobalt chloride

Baidu encyclopedia-sodium hydroxide