1.3 transition metals

Question 1

what block are the transition metals

Answer 1

d

Question 2

do transition metals have full d subshells?

Answer 2

no, only partially filled

Question 3

which principle does the filling of d orbitals follow

Answer 3

the aufbau

Question 4

what two transition metals are an exception for filling up following the aufbau principle, and why

Answer 4

chromium and copper
they have a special stability associated with the d subsjell being half filled or completely filled

Question 5

which electrons are lost if atoms from the first row of transition metals form ions

Answer 5

the 4s electrons. not the 3d!

Question 6

when is an element said to be in a particular oxidation state

Answer 6

when it has a specific oxidation number

Question 7

what is the oxidation number of uncombined elements

Answer 7

0

Question 8

what is the oxidation number of ions containing single atoms

Answer 8

one that is the same as the charge on the ion

Question 9

what is the usual oxidation number of oxygen

Answer 9

-2

Question 10

what is the usual oxidation number of hydrogen

Answer 10

1

Question 11

what must the sum of all the oxidation numbers of all the atoms in a neutral atom add up to

Answer 11

0

Question 12

what must the sum of all the oxidation numbers of all the atoms in a polyatomic ion be equal to

Answer 12

the charge on the ion

Question 13

can a transition metal have different oxidation states in its compounds

Answer 13

yes

Question 14

can the compounds of the same transitio nmetal in different oxidation states have different colours

Answer 14

yes they may

Question 15

what can oxidation be defined as

Answer 15

an increase in oxidation number

Question 16

what can reduction be considered as

Answer 16

a decrease in oxidation number

Question 17

what can the changes in oxidation number of transition metals be used to determine

Answer 17

whether oxidation or reduction has occurred

Question 18

what compounds containing metals are often recognized as oxidising agents

Answer 18

those with high oxidation states

Question 19

which compounds containing are often recognized as reducing agents

Answer 19

those with low oxidation states

Question 20

what are ligands

Answer 20

• negative ions
• molecules with non bonding pairs

Question 21

how can ligands be classified

Answer 21

monodentate, bidentate, hexadentate

Question 22

is it possible to deduce the ligand classification from a formula or structure of the ligand or complex

Answer 22

unfortunately yes

Question 23

what is the coordination number

Answer 23

the total number of bonds from the ligands to the central transition metal

Question 24

when are d orbitals no longer degenerate

Answer 24

in a complex of a transition metal

Question 25

when does the splitting of d orbials to higher and lower energies occur

Answer 25

when the electrons present in the approaching ligands cause the electrons in the orbitals lying along the axes to be repelled

Question 26

what are strong field ligands

Answer 26

ligands that cause a large difference in energy between subsets of d orbitals

Question 27

what are weak field ligands

Answer 27

ligands that cause a small difference in energy between subsets of d orbitals

Question 28

how can ligands be placed

Answer 28

in order of their ability to split d orbitals

Question 29

what is the spectrochemical series

Answer 29

the order that ligands are placed according to their ability to split d orbitals

Question 30

how can the colours of many transition metal complexes be explained

Answer 30

in terms of d-d transitions

Question 31

when is light absorbed

Answer 31

when electrons in lower energy d orbital are promoted to d orbital of higher energy

Question 32

when is the complementary colour observed

Answer 32

when one light of one colour is absorbed

Question 33

when light of one colour is absorbed, what is observed

Answer 33

the complementary colour

Question 34

when do electrons transition to higher energy levels

Answer 34

when energy corresponding to the ultraviolet or visible regions of the electromagnetic spectrum is absorbed

Question 35

can transition metals act as catalysts

Answer 35

yes

Question 36

are heterogenous catalysts in different states to the reactants

Answer 36

yes

Question 37

how can heterogenous catalysts be explained

Answer 37

in terms of the formation of activated complexes and the adsorption of reactive molecules onto active sites

Question 38

what is the presence of unpaired d electrons or unfilled d orbitals thought to allow

Answer 38

activated complexes to form

Question 39

what can the formation of activated complexes provide

Answer 39

reaction pathways with lower activation energies compared to the uncatalysed reaction

Question 40

are homogenous catalysts in the same or different state as the reactants

Answer 40

same

Question 41

how can homogenous catalysts be explained

Answer 41

in terms of changing oxidation states with the formation of intermediate complexes