Question

Электронная формула 1s2; 2s22p6; 3s2 3p63d10; 4s2 4p6 4d5;5s2 1)Cu 2)Tc 3) As 4)At

Answer 1

В таблице Менделеева все написано сверху под элементом

Answer 2

The electronic configurations you've provided are as follows:

1. Cu (Copper): [Ar] 3d10 4s1
2. Tc (Technetium): [Kr] 4d5 5s2
3. As (Arsenic): [Ar] 3d10 4s2 4p3
4. At (Astatine): [Xe] 4f14 5d10 6s2 6p5

Please note that the electron configurations are represented by the principal quantum number followed by the type of orbital and the number of electrons in that orbital. For example, 3d10 means there are 10 electrons in the d-orbital of the third energy level. The notation in square brackets indicates the noble gas configuration before the valence electrons.