Question

How can nuclear charge decrease effectively?

Answer 1

The periodic table tendency for effective nuclear charge: Increase across a period (due to increasing nuclear 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

cause the electrons get farther and farther away from the nucleus, normally the effective nuclear charge (enc) would decreases as you go down a group. however, the charge of the nucleus increases as more protons are present in the respective elements.

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