Physical property

Lithium chloride is a white crystal, easily soluble in water, and its solubility under standard conditions is 67g / 100ml water. It is also easily soluble in ethanol, acetone, pyridine and other organic solvents, but difficult to dissolve in ether. Therefore, in the preparation of alkyl lithium, if chlorohalogenated hydrocarbon is used to precipitate lithium chloride in ether, free alkyl lithium reagent can be obtained (lithium bromide and lithium iodide form adducts with alkyl lithium to act as stabilizer). The melting point is 605 ℃, the boiling point is 1350 ℃, and the lattice energy is 853 kJ / mol.

Chemical property

The aqueous solution is neutral or slightly alkaline. Lithium metal and chlorine can be produced by electrolysis anhydrous lithium chloride. Lithium can also be deposited from pyridine solution electrolyzed with anhydrous lithium chloride.

Lithium chloride can form a variety of hydrates. From the phase diagram of licl-h2o, it can be clearly seen that there are LiCl · H2O, LiCl · 2H2O, LiCl · 3H2O, LiCl · 5H2O and so on. The amount of crystallized water depends on the crystallization temperature. The lower the temperature, the higher the degree of hydration.

Li can form complex ion [li (NH3) 4] with ammonia, so the solubility of ammonia in lithium chloride solution is much higher than that in water. Like other ionic chlorides, lithium chloride can also supply chloride and lithium ions in aqueous solution, and precipitate insoluble chloride or lithium salt with some other ions, such as silver chloride:

LiCl+AgNO3→AgCl↓+LiNO3

Solubility

Lithium chloride is a sodium chloride type structure, and its chemical bonds are not typical ionic bonds. Therefore, it can be dissolved in many organic solvents and can form adducts with ethanol, methanol and amines. This property can be used to separate lithium chloride from alkali metal chlorides.

The solubility of lithium chloride is much higher than that of other chlorides (83g / 100mL, 20 ℃) due to the smaller ionic radius and higher hydration energy of lithium. Its aqueous solution is alkaline.