Question

Describe the general trends in the following properties of the elements in Groups 13 and 14.

Nature of halides

Answer 1

Except thallium, All the elements of the boron family combine with three atoms of halogens to form trihalides. All these halides exist as molecular species with hybridisation of sp². All the trihalides are Lewis acid and their acidic strength of trihalides of boron is in order: Bf₃ < BCl₃ < BBr₃ < Bl₃. In group-14, except carbon, all group 14 elements on reaction with halogens form tetra halides where central metal atom shows the sp³ hybridisation state and corresponding tetrahedral shape.

There are few exceptions also, SnF₄ and Pf₄ are ionic in nature, while the rest are covalent compounds.