What color is magnesium hydroxide precipitation

The precipitate of magnesium hydroxide is white.
Magnesium hydroxide is a white amorphous powder. It is also called caustic magnesite, light burned magnesia, etc. The suspension of magnesium hydroxide in water is called magnesium hydroxide emulsion, which is called magnesium emulsion for short. Magnesium hydroxide is a colorless hexagonal column crystal or white powder, which is insoluble in water and alcohol, soluble in dilute acid and ammonium salt solution, and the aqueous solution is weakly alkaline.
The solubility in water is very small, but the part dissolved in water is completely ionized. The concentration of saturated aqueous solution is 1.9 mg/l (18 ℃). When heated to 350 ℃, the water will lose its magnesium oxide. The natural mineral brucite of magnesium hydroxide.
It can be used for making sugar and magnesium oxide. Because magnesium hydroxide is rich in nature, and its chemical properties are similar to aluminum, users began to use magnesium hydroxide to replace aluminum chloride for deodorant products. It is used as an analytical reagent and also in the pharmaceutical industry.
Application field:
1. Magnesium hydroxide is an excellent flame retardant for plastic and rubber products. In terms of environmental protection, it can be used as flue gas desulfurizer to replace caustic soda and lime as neutralizer of acid containing wastewater. It is also used as oil additive to prevent corrosion and desulfurization. In addition, it can also be used in the refining of electronic industry, medicine, granulated sugar, as thermal insulation materials and manufacturing other magnesium salt products.
2. Magnesium hydroxide has excellent buffering property, reactivity, adsorbability, thermal decomposition performance, etc. It can not only be used as chemical materials and intermediates, but also be used as a green flame retardant and additive in rubber, plastic, fiber and resin industries. Magnesium hydroxide is mainly used as flame retardant, acid wastewater treatment agent, heavy metal remover, flue gas desulfurization agent in the field of environmental protection. [2] 
3. The product can be used as flame retardant or flame retardant filler and added to polyethylene, polypropylene, polystyrene and ABS resin. It has good flame retardancy and smoke suppression effects. The amount of addition is 40-20 parts.
However, it is necessary to treat the particle surface with anionic surfactant, such as cheap high-class fatty acid alkali metal salt or alkyl sulfate and sulfonated succinate, with the dosage of about 3%. The product is also used in the manufacture of magnesium salt, refining of granulated sugar, pharmaceutical industry, daily chemical industry, etc.
4. The product is also used in the manufacture of magnesium salt, refining of granulated sugar, pharmaceutical industry, daily chemical industry, etc. At the same time, the water vapor it emits can also be used as a smoke suppressant. Magnesium hydroxide is an excellent flame retardant with triple functions of flame retardancy, smoke suppression and filling in the rubber and plastic industry.
5. The emulsion suspension of magnesium hydroxide is used as an antacid and a laxative in medicine.
Principle of sedimentation:
The process of producing a separable solid phase from the liquid phase, or insoluble substances separated from the supersaturated solution. Precipitation refers to the formation process of a new condensed phase, or the deposition process due to the addition of precipitator to make some ions become insoluble compounds. The chemical reaction that produces precipitation is called precipitation reaction.
The precipitation and dissolution of substances is an equilibrium process, and the solubility product constant Ksp is usually used to judge whether the insoluble salts are precipitated or dissolved. The solubility product constant refers to that the product of the concentration of each ion constituting the precipitation is a constant in the saturated solution of insoluble electrolyte at a certain temperature.
This relationship is often used in analytical chemistry to reduce the precipitation solubility by adding the same ions, so that the measured components remaining in the solution can be ignored.