Halide-main group elements

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The alkali metals combine directly with halogens under appropriate conditions forming halides of the general formula, MX (X = F, Cl, Br or I).
A halide ion is a halogen atom bearing a negative charge. The halide anions are fluoride (F−), chloride (Cl−), bromide (Br−), iodide (I−) and astatide (At−). Such ions are present in all ionic halide salts. Halide minerals contain halides.
All these halides are colourless, high melting crystalline solids having high negative enthalpies of formation. 
Halide compounds such as KCl, KBr and KI can be tested with silver nitrate solution, AgNO3. The halogen will react with Ag+ and form a precipitate, with varying colour depending on the halogen:
  • AgF: no precipitate
  • AgCl: white
  • AgBr: creamy (pale yellow)
  • AgI: green (yellow)
For organic compounds containing halides, the Beilstein test is used. 
Different reaction;-



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