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no of waves for 3rd electron of lithium atom is |
Answer» <p>The number of waves for 3rd electron of lithium atom are 2.</p> <p>Explanation</p><p>As in the case of helium, the increase in nuclear charge to +3 produces a correspondingreductionin the size of the lithium 1sorbital. In sharp contrast to this compact inner orbital is the very large and very diffuse cloud of the outer 2selectron. There are two reasons why this 2scloud is so large.The first reason is that the principalquantum numbernhas increased from 1 to 2.</p><p>Lithium's, 2selectron cloud is bigger than 1seven in the hydrogen atom with a nuclear charge of only +1. A second reason is that the two 1selectrons are usually closer to the nucleus than the 2selectron. These two 1selectrons have the effect ofscreeningorshieldingthe outer electron from the full attractive force of the +3 charge on the nucleus. When the 2selectron is some distance from the nucleus, it “sees” not only the +3 charge on the nucleus but also the two negative charges close by.</p><p> The overall effect is almost as though two of the three positive charges on the nucleus are canceled, leaving a net charge of + 1 to hold the outer electron to the atom. This situation can also be described by saying that theeffective nuclear chargeis close to +1.</p> | |