Question

Почему седьмой период в таблице менделеева называют незавершенным? Помогите пожалуйста!!

Answer 1

Потому что у нее не хвотает один электрон до совершения

Answer 2

The Seventh Period in Mendeleev's Periodic Table

The seventh period in Mendeleev's periodic table is often referred to as "incomplete" because it is not fully filled with elements. This period is located below the sixth period and is the longest period in the periodic table. It consists of 32 elements, starting with atomic number 87 (francium) and ending with atomic number 118 (oganesson).

The reason why the seventh period is considered incomplete is that it does not follow the pattern of filling electron shells that is observed in the previous periods. In the first six periods, the electron shells are filled in a specific order: 2, 8, 8, 18, 18, and 32. However, in the seventh period, the electron shells are not completely filled according to this pattern. This is due to the increasing complexity of electron configurations and the limitations of the periodic table's structure.

It is important to note that the elements beyond atomic number 118 (oganesson) have not been synthesized or observed in nature. They are highly unstable and have extremely short half-lives, making them difficult to study Therefore, the seventh period remains incomplete in terms of known elements.

Conclusion

In summary, the seventh period in Mendeleev's periodic table is considered incomplete because it does not follow the pattern of filling electron shells observed in the previous periods. It is the longest period in the periodic table and consists of 32 elements, but it is not fully filled with elements according to the expected pattern.