How would you account for the following? (i) The d1 configuration is very unstable in ions.
How would you account for the following? (i) The d1 configuration is very unstable in ions.

(i) The ions in dconfiguration tend to lose one more electron to get into stable d0 configuration. Also, the hydration or lattice energy is more than sufficient to remove the only electron present in the d-orbital of these ions. Therefore, they act as reducing agents.