Lithium bromide (LiBr) is a stable inorganic salt with core chemical characteristics of high stability, extremely strong water absorption, neutral to slightly alkaline aqueous solution, corrosive to metals, decomposable at high temperatures, and capable of forming adducts with ammonia/amines.
1、 Basic structure and stability
      Molecular formula: LiBr (alkali metal halide, similar to NaCl).
      Thermal stability: Stable from room temperature to 500 ℃; Strong heat (>600 ℃) decomposes in the air, releasing Br ₂, and residual Li ₂ CO ∝/Li ₂ O is alkaline.
      Storage stability: does not decompose or deteriorate in dry air; Extremely prone to deliquescence, requires sealed and dry storage.
2、 Hydration and dissolution characteristics
      Hydrates: Common LiBr · H ₂ O, LiBr · 2H ₂ O, LiBr · 3H ₂ O; lose 1 molecule of water at 44 ℃, and obtain anhydrous LiBr at>160 ℃.
      Solubility (water): approximately 61 g/100 mL at 25 ℃, reaching 254 g/100 mL at 90 ℃; The solubility is much higher than NaCl, the vapor pressure of the solution is lower, and the hygroscopicity is extremely strong (the core principle of refrigeration).
      Organic solvents: soluble in ethanol, ether, methanol, acetone, and ethylene glycol; Slightly soluble in pyridine; Insoluble in liquid bromine.
3、 Properties of aqueous solution
      Acidity and alkalinity: neutral to slightly alkaline (pH ≈ 7-8), Li ⁺ hardly hydrolyzes.
      Corrosivity: Strong corrosion to steel, copper, and other materials (exacerbated by oxygen); Vacuum+corrosion inhibitor (lithium chromate/lithium molybdate) can significantly inhibit corrosion.
      Solubility: Hot concentrated solution can dissolve cellulose.
4、 Chemical reaction characteristics
      Addition with ammonia/amine: LiBr · nNH VNet (n=1-4) are generated, such as LiBr · NH VNet and LiBr · 4NH VNet.
      Dissolve with metal halides: Form soluble double salts with CuBr ₂, HgBr ₂, SrBr ₂, etc.
      Molten corrosion: High temperature molten corrosion of glass, ceramics, and platinum vessels.
      Prohibited substances: Strong oxidants, strong acids, strong bases (avoid violent reactions).
5、 Key application related properties
      High boiling point (1265 ℃), difficult to evaporate: suitable as an absorbent for absorption refrigeration machines (water as refrigerant).
      Non toxic and stable: Industrial and commercial refrigeration systems are safe and reliable.

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