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TSR Wiki > Study Help > Subjects and Revision > Revision Notes > Chemistry > Transition Metals

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Contents 1 Transition Elements 2 Properties of transition elements 3 Complexes 4 Definitions 5 Electronic Configuration 6 Oxidation States of Vanadium 7 Comments

Transition Elements

A transition element is a metal with an ion or a compound with a partially filled d subshell.

Zinc is not a transition metal but is a d block element because it has a full d subshell. This is shown because its compounds are usually white.

Properties of transition elements

• Coloured compounds and ions
• Form complex ions
• Have catalytic properties
• Variable oxidation states
• High melting point
• High density
• High tensile strength
• Show paramagnetism

Complexes

A complex is formed when a transition metal ion is surrounded by ligands which dative covalent bond with it by donating lone pairs of electrons into vacant d orbitals. The d electrons of the metal ion do not take part in ligand bonding.

Definitions

• d block element: an element whose highest energy electrons are in the d orbital

• Transition metal/element: one which forms stable ions which have one or more unpaired electron in the d orbital.

Electronic Configuration

Transition metals have full 1s, 2s, 2p, 3s and 3p orbitals. i.e. 18 electrons. Hence, they are sometimes written as: E.g. Sc [Ar] 3d1 4s2 - since Ar has 18 electrons.

NOTE: the 4s electrons are lost and gained BEFORE the 3d orbitals.Vanadium

Vanadium, like many other transition metals can form various oxidation states. This means it can be used as a catalyst because it can readily gain or lose electrons i.e. be reduced or oxidised i.e. undergo redox.

Oxidation States of Vanadium

+5 in VO2+ (yellow) +4 in VO2+ (blue) +3 in V3+ (green) +2 in V2+ (lavender)

NOTE: If the question mentions the reduction of vanadium and notes the colour change as being yellow to green to blue to green to lavender, the first green is simply a mixture of the yellow VO2+ and the blue VO2+ ions.

Comments