Question

1.) The molecule XCl3 is pyramidal. In which group in the periodic table is element X found? If the molecule were planar triangular, in which group would X be found? If the molecule were T-shaped, in which group would X be found? Why is it unlikely that element X is in Group 6A (16)?

Answer 1

If XCl₃ is pyramidal then X belongs to group 15 of periodic table, e.g. NCl₃ .Now if XCl₃ is planer triangular then X belongs to group 13, e.g. BCl₃ . And if XCl₃ is T-shaped then X belongs to group 17 of the periodic table, e.g. ICl₃ . But X can not be a member of group 16 because the element of gruop 16 have 4 valance electrons. Out of which 3 chlorine from 3 covalent bond with X and there will be one unpaired electron.Thus this compound behaves as a free radical and becomes unstable.so group 16 elements can only form the compound of the type XCl₄ .