Question

9. Write electronic configuration of 26Cr 29Cu​

Answer 1

Answer:

This is expected that the configuration of copper is 3d

9

4s

2

. However, it turns out that the 3d

10

4s

1

configuration is more stable, because that way the 3d subshell is full, which is a far more stable arrangmemnt than 3d

9

.

Due to extra stability of half filled and full filled orbital, Cu have configuration 1s

2

2s

2

2p

6

3s

2

3p

6

3d

10

4s

1

4p

0

.

Answer 2

Answer:

1s2 2s2 2p6 3s2 3p6 3d6 4s2 -- Cr

1s2 2s2 2p6 3s2 3p6 3d10 4s1 --- Cu