for d block elements the last electron enters to which subshells
Dear Student,
The d-block elements exist in groups 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 of the periodic table and d-block elements are the transition metals.
The d–orbitals of the last but one energy level in their atoms get electrons important to the three columns of the transition metals, are 3d, 4d and 5d.
The electronic configuration of transition elements is (n-1)d1-10ns1-2. The (n-1) is inner shell,the d-orbitals have 1 to 10 electrons and the s-orbital of the outermost shell (n) have one or two electrons.
After filling of 4s orbital,sequentially with two electrons at atomic number 19 and 20, the next incoming electron goes to 3d orbital instead of 4p,because of the 3d orbital is of lower energy than the 4p orbital. After calcium, electron is filled in the d- subshell in the next element.Then half-filled and ful-filled subshells are more stable.All the d-block elements have same number of electrons in the outermost shell. Thus, they show comparable chemical properties.
Regards,
The d-block elements exist in groups 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 of the periodic table and d-block elements are the transition metals.
The d–orbitals of the last but one energy level in their atoms get electrons important to the three columns of the transition metals, are 3d, 4d and 5d.
The electronic configuration of transition elements is (n-1)d1-10ns1-2. The (n-1) is inner shell,the d-orbitals have 1 to 10 electrons and the s-orbital of the outermost shell (n) have one or two electrons.
After filling of 4s orbital,sequentially with two electrons at atomic number 19 and 20, the next incoming electron goes to 3d orbital instead of 4p,because of the 3d orbital is of lower energy than the 4p orbital. After calcium, electron is filled in the d- subshell in the next element.Then half-filled and ful-filled subshells are more stable.All the d-block elements have same number of electrons in the outermost shell. Thus, they show comparable chemical properties.
Regards,