Which of the following transition metals have more than one oxidation state?
(a) Ti
(b) V
(c) Cr
(d) Zn

Transition metals are elements found in the d-block of the periodic table, characterized by their ability to form variable oxidation states. They typically have partially filled d-orbitals, which allow them to lose different numbers of electrons when forming compounds. This property is crucial for understanding their chemical behavior and reactivity.

An oxidation state, or oxidation number, indicates the degree of oxidation of an atom in a compound. It reflects the number of electrons lost, gained, or shared when forming chemical bonds. Transition metals often exhibit multiple oxidation states due to their ability to lose different numbers of d and s electrons, which is essential for predicting their chemical reactions.

Different transition metals have characteristic oxidation states that they commonly exhibit. For example, titanium (Ti) can have oxidation states of +2, +3, and +4, while vanadium (V) can have +2, +3, +4, and +5. Understanding these common oxidation states helps in identifying which transition metals can participate in various chemical reactions and form different compounds.