Transition Metals

Question 1

What are d block transition metals?

Answer 1

Metals with an incomplete d sub shell in at least one of their ion.
4s electrons are lost before 3d electrons during ionisation to positive ions.
filling d orbitals follow the Aufbau principle. ( with the exception to chromium and copper atoms

Question 2

What is the oxidation number of all elements?

Answer 2

0

Question 3

What is the oxidation number of monatomic ions?

Answer 3

it is equal to their charge

Question 4

In most compounds, what is the oxidation number of H & O

Answer 4

Hydrogen = +1 (except hydrides where H is -1)
Oxygen = -2 (except peroxides where O is -1)

Question 5

What must the sum of all the oxidation numbers in a molecule equal?

Answer 5

0

Question 6

What must the sum of all the oxidation numbers in a polyatomic ion equal?

Answer 6

The charge on the ion

Question 7

How are oxidation numbers written?

Answer 7

Sign first then number after

Question 8

What has occurred if there is an increase in oxidation number?

Answer 8

Oxidation has occurred

Question 9

What has occurred if there is a decrease in oxidation number?

Answer 9

Reduction has occurred

Question 10

What compounds tend to be oxidising agents

Answer 10

Compounds containing metals with high oxidation numbers, these oxidising agents are reduced to a lower oxidation number.

Question 11

What compounds tend to be reducing agents

Answer 11

Compounds containing metals with low oxidation numbers, agents are oxidised themselves to increase oxidation number

Question 12

What is a common oxidation state in transition metals and why?

Answer 12

It is very common to have a oxidation state of +2 as the 4s^2 electrons are lost before 3d electrons.

Question 13

What is a transition metal complex?

Answer 13

Compounds made of transition metal ions bonded covalently to ligands.

Question 14

What is a ligand?

Answer 14

A ligand is a molecule or ion electron donor which bonds to the metal ion by the donation of one or more electron pairs to unfilled metal ion orbitals.

Question 15

What is classification?

Answer 15

Ligands can be classified according to the number of atoms they use to bond to a transition metal ion.

Question 16

What are the neutral ligands?

Answer 16

Ammonia ( NH3 )
Water ( H20 )

Question 17

Is an NH4 ligand positive or negative?

Answer 17

Positive

Question 18

What are the ligands you have to remember?

Answer 18

Halide ions ( group 7 ) are negative
Cyanide ion (CN) -1
Nitrite ion ( NO2- ) -1
Oxalate ion ( C2O4 ) is -2
NH4 +1

Question 19

What is a monodentate ligand?

Answer 19

Ligands which donate 1 pair of electrons

Question 20

What are bidentate ligands?

Answer 20

Ligands which donate 2 pairs of electrons ( the 2 pairs of electrons must be on different parts of the molecule, not thew same atom )

Question 21

What is a polydentate ligand?

Answer 21

A ligand has more than one pair of electrons donated to the central metal ion.

Question 22

What is the coordination number?

Answer 22

The number of bonds of the ligand(s) to the central ion is called the coordination number.

Question 23

what is the coordination number of (Cu(h2o)6)2+ and why?

Answer 23

6

the central Cu2+ ion is surrounded by 6 water molecules.
these are hexandentate ligands

Question 24

What are the steps involved in writing the formula Of complexes?

Answer 24

1) Formula of complex ions are written in square brackets
2)Metal symbol comes first
3) negative ligands come next
4)neutral ligands come next
5)overall change is written after square brackets

Question 25

Are transition metals usually + or - ? and why?

Answer 25

+
because they give electrons

Question 26

Are non metals usually + or - ? and why?

Answer 26

-

because they receive electrons

Question 27

what are the prefixes used in each number of the ligands?

Answer 27

1 - mono (optional)
2-di
3-tri
4-tetra
5-penta
6-hexa
7-hepta
8-octa

Question 28

if a complex has a negative charge, what does the metal end in when naming these complexes?

Answer 28

-ate
eg, cobalt becomes cobaltate
iron becomes ferrate
manganese becomes manganate

Question 29

When writing complexes, how is the oxidation state of the metal written?

Answer 29

After the metal, in roman numerals in brackets

Question 30

What is a dative covalent bond?

Answer 30

When both electrons in a covalent bond come from the same atom, a dative covalent bond is formed.

Question 31

what is a transition metal?

Answer 31

A metal with an incomplete d sub shell in at least one of its ions.

Question 32

what 2 elements break the aufbau principle and why?

Answer 32

Chromium and copper due to increased stability of having a fully or half filled sub shell.

Question 33

what two elements are not technically transition metals and why?

Answer 33

Scadium and Zinc as they do not form ions with incomplete d sub shells.