Transition Metals

Question 1

Transition element

Answer 1

An element that forms at least one stable bond with an incomplete d subshell of electrons

Question 2

Why are scandium and zinc not tms?

Answer 2

Scandium only forms Sc3+ (3d 0) in all its compounds

Zinc only forms Zn2+ (3d 10) in all its compounds

Question 3

Four chemical properties of TMs

Answer 3

Variable oxidation states - can take part in many redox reactions

Coloured

Catalysis - show catalytic activity

Complex ion formation

Question 4

Complex ion

Answer 4

A central TM ion surrounded by molecules or ions (ligands) by coordinate bonding

Question 5

Coordinate bond

Answer 5

Where one atom provides both the electrons for covalent bonding

Question 6

Ligand

Answer 6

An ion or molecule which can donate a lone electron pair forming a coordinate bond with the TM

Question 7

Monodentate ligand

Answer 7

Each ligand only forms one coordinate bond - only one pair of elections available for bonding

Question 8

Bidentate ligand

Answer 8

Each ligand forms two coordinate bonds with the TM

Lone pair available on two different atoms

Question 9

multidentate ligand

Answer 9

A ligand with more than two lone pairs of electrons available to form coordinate bonds

Question 10

Examples of monodentate ligands

Answer 10

H2O (octahedral)

Cl (tetrahedral/Square planar)

NH3 (octahedral)

CN (tetrahedral/square planar)

Square planar when central ion either Ni or Pt

Question 11

When are Cl and CN square planar instead of tetrahedral?

Answer 11

Square planar when central ion either Ni or Pt

Question 12

Coordination number

Answer 12

The number of coordinate bonds formed to a central ion

Question 13

Aqua ion

Answer 13

If you dissolve the salt of a TM in water - become surrounded by water molecules

Question 14

Lewis acid

Answer 14

Electron pair acceptor

Question 15

Lewis base

Answer 15

Electron pair donor

Question 16

Bidentate ligand examples

Answer 16

Ethanedioate ion (2-)

1,2-diaminoethane

Question 17

Multidentate ligand example

Answer 17

EDTA 4-

Question 18

How does CO affect haemoglobin?

Answer 18

Normally O2 acts as a ligand and bonds weakly to the haemoglobin to be carried in blood

CO is a stronger ligand than O2. Meaning it takes O2 place on the haemoglobin and bonds to it irreversibly

Question 19

Stereoisomerism:

Square planar is…

Answer 19

Cis/trans isomerism

Question 20

Stereoisomerism:

Octahedral with monodentate ligands is…

Answer 20

Cis/trans!

Question 21

Stereoisomerism:

Octahedral with bidentate ligands

Answer 21

Optical isomerism

Question 22

Ligand substitution reaction

Answer 22

When a ligand in a complex is replaced by another ligand

Question 23

Ligand substitution:

Why are some 🔼H = 0 ?

Answer 23

The number and type of coordinate bond remains the same