Question

Why does nuclear charge decrease down the group?

Answer 1

The periodic table tendency for effective nuclear charge: Increase across a period (due to increasingnuclear charge with no accompanying increase in shielding effect). Decrease down a group (although nuclear charge increases down a group, shielding effect more than counters its effect)

Answer 2

Answer:-

Due to Size

As we go down the group no. Of electrons in the inner shell keep on increasing, now the inner shell electron always repels the electron in the outer shell away from the nucleus and so as we go down the net charge faced by each valence shell electron after the battle between the repulsive and attractive forces,called “effective nuclear charge”, decreases as the number of electrons in inner orbits increase faster than the nuclear charge at center which also results in increase in size down the group.

I hope it will be vale to you now, plz understand care fully that decrease in effective nuclear charge cause the size of atom to increase down the group and its not the other way around.

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