Question

What is the trend in reactivity of the halogens?

Answer 1

The trend of reactivity of halogens decreases down the group. As halogens are non metals, hence they gain electrons when reacted with metals, when the halogen react, they take an extra electron in their outer shell hence form negatively charged ion.

As their radius increases down the group, distance between the nucleus and valence shell electron increase which make it harder to gain or attract any further electron in the valence shell because of weak attraction with nucleus, which reduces the reactivity down the group.

Answer 2

Answer :

The reactivity of Group 7 components diminishes down the gathering. Non-metal ion gain electrons when they respond with metals. At the point when a halogen molecule responds, it increases one electron into their most astounding possessed vitality level (external shell) to frame an independently negative charged particle.

As we go down the gathering , an extra electron shell is included in this manner expanding the nuclear radii of the molecule. The electrons in the external shell move further far from the core as we go down the gathering and the fascination compel between the electrons and the core end up more fragile and flimsier .

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