The oxidation state of the d-block elements can vary from -2 to +8, depending on the element and the compound it is in. Most of the d-block elements have an oxidation state of +2, +3, +4, or +6 in their compounds.
Oxidation state of d block elements – ഡി ബ്ലോക്ക് മൂലകങ്ങളുടെ ഓക്സിഡേഷൻ അവസ്ഥ