The configuration of Cr atom is 3d^(5)4s^(1) but not 3d^(4)4s^(2) due to reason R_(1) and the configuration of Cu atom is 3d^(10)4s^(1) but not 3d^(9)4s^(2) due to reason R_(2).R_(1) and R_(2) are:

The configuration of Cr atom is 3d^(5)4s^(1) but not 3d^(4)4s^(2) due

1.	The configuration of Cr atom is 3d^(5)4s^(1) but not 3d^(4)4s^(2) due to reason R_(1) and the configuration of Cu atom is 3d^(10)4s^(1) but not 3d^(9)4s^(2) due to reason R_(2).R_(1) and R_(2) are:
Answer» `R_(1):` The exchange energy of `3d^(5)4s^(1)`: is GREATER than that of `3d^(4)4s^(2)` `R_(2):` The exchange energy of `3d^(10)4s^(1)` is greater than that of `3d^(9)4s^(2)`. `R_(1)`: `3d^(5)4s^(1)` and `3d^(4)4s^(2)` have same EXHANGE energy but `3d^(5)4s^(1)` is spheriaclly symmetrical. `R_(2)`: `3d^(10)4s^(1)` is also shpherically symmetrical. `R_(1)`: `3d^(5)4s^(1)` has GRATER exhange energy than `3d^(4)4s^(2)`. `R_(2):3d^(10)4s^(1)` has spherical symmetry. `R_(1):3d^(5)4s^(1)` has greater energy than `3d^(4)4s^(2)`. `R_(2):3d^(10)4s^(1)` has greater energy than `3d^(9)4s^(2)`. SOLUTION : `3d^(5)4s^(1)` is correct because it has greater exchange possibilities of unpaired electron. `3d^(10)4s^(1)` is correct because `3d^(10)` orbitals are spherically symmetrical.