group-17 elements part-1

What is the highest oxidation state exhibited by group 17 elements ?

(a) What is a group in the periodic table? In which part of a group would you separately expect elements to have (i) the greatest metallic character (ii) the largest atomic size? (b) In what respects do the properties of group 1 elements differ from those of group 17 elements? Explain with examples by taking one element from each group. (c) From the standpoint of atomic structure, what determines which element will be the first and which the last in a period of the periodic table? (d) Explain why, the properties of elements are repeated after 2,8,18 and 32 elements in the periodic table.

Group 17 elements are known as

Group 17 elements are called Halogens ?

The increasing order of reactivity among group 1 elements is LiltNaltKltRbltCs whereas that among group 17 elements is FgtClgtBrgtI . Explain.

Arrange group 17 elements in the correct order of enthalpy of bond dissociation:

The colour of the X_(2) molecules of group 17 elements changes gradually from yellow to violet down the group. This is due to