C24- Transition elements

Question 1

Transition element definition

Answer 1

d block elements that form at least one ion with a partially filled d orbital

Question 2

Why is scandium or zinc not a transition metal

Answer 2

Forms an ion with no electrons in a d orbital

Question 3

What is the overall charge of a complex ion formed from

Answer 3

sum of charge of metal ion and charges on ligands

Question 4

Key things needed when writing the formula of a complex ion

Answer 4

square brackets

charge

Question 5

What is a ligand

Answer 5

a molecule which bonds to metal ions

Question 6

type of bond formed between ligands and transition metals

Answer 6

coordinate bonds

dative covalent bonds

Question 7

what is the coordination number

Answer 7

the number of coordinate bonds in a complex ion

Question 8

what is a monodenate ligand

Answer 8

one lone pair

forms one coordinate bond

can be charged or neutral

Question 9

what is a bidenate ligand

Answer 9

ligands that can form two coordinate bonds since they donate two lone pairs of electrons from two donor atoms

species with two lone pairs

Question 10

what is a polydenate ligand

Answer 10

a ligand that can form 3 or more coordinate bonds by donating at least 3 pairs of electrons to the metal ion

Question 11

Example of polydentate ligand

Answer 11

EDTA 4-

forms 6 coordinate bonds

Question 12

uses of polydentate ligands

Answer 12

can be used to remove metal iokn from solution

increases entropy

Question 13

octahedral ion bond angle`

Answer 13

90

Question 14

What types of transition elements form the square planar shape

Answer 14

ones with electrons in their outermost d orbital

Question 15

examples of metals that form square planar ions

Answer 15

platinum

gold

palladium

Question 16

Cu2+ aqueous ion colour

Answer 16

blue

Question 17

Fe2+ aqueous ion colour

Answer 17

green

Question 18

Fe3+ aqueous ion colour

Answer 18

yellow

Question 19

Mn2+ aqueous ion colour

Answer 19

pale pink

Question 20

Cr3+ aqueous ion colour

Answer 20

violet

Question 21

Cu2+ precipitate formula and colour

Answer 21

Cu(OH)2

pale blue

Question 22

Fe2+ precipitate formula and colour

Answer 22

Fe(OH)2

green

Question 23

Fe3+ precipitate formula and colour

Answer 23

Fe(OH)3

orange/ brown

Question 24

Mn2+ precipitate formula and colour

Answer 24

Mn(OH)2

light brown

Question 25

Cr3+ precipitate formula and colour

Answer 25

Cr(OH)3 green

Question 26

Which ligand precipitation reaction forms precipitate that redissolves in excess OH-

Answer 26

Cr3+ forms a green solution not a green precipitate

Question 27

Cu2+ aqueous ligand formula

Answer 27

[Cu(H2O)4(OH)2]

Question 28

Fe2+ aqueous ligand formula

Answer 28

[Fe(H2O)4(OH)2]

Question 29

Fe3+ aqueous ligand formula

Answer 29

[Fe(H2O)3(OH)3]

Question 30

Mn2+ aqueous ligand formula

Answer 30

[Mn(H2O)4(OH)2]

Question 31

Cr3+ aqueous ligand formula

Answer 31

[Cr(H2O)3(OH)3]

Question 32

Cr3+ redissolving equation

Answer 32

[Cr(H2O)3(OH)3](s)+3OH- --> [Cr(OH)6] (aq) + 3H2O

Question 33

Effect of adding excess NH3 to copper ligand precipitate

Answer 33

precipitate redissolves so solution turns form pale to dark blue

Question 34

Effect of adding excess NH3 to copper ligand precipitate reaction type

Answer 34

ligand substitution

Question 35

Effect of adding excess NH3 to copper ligand precipitate equation

Answer 35

[Cu(H2O)6]2+ + 4NH3 --> [Cu(NH3)4(H2O)2]2+ + 4H2O

Question 36

Effect of adding conc HCl to blue hexaaqua solution

Answer 36

blue to yellow colour change can have a green intermediate

Question 37

Effect of adding conc HCl to blue hexaaqua solution equation

Answer 37

[Cu(H2O)6]2+ +4Cl- --> [CUCL4]2- +6H2O

Question 38

[Cr(H2O)6] solution colour

Answer 38

violet

Question 39

[Cr(H2O)6] solution in prescence of sulfate

Answer 39

green [Cr(H2O)5SO4]+ forms

Question 40

[Cr(H2O)6] in excess ammonia

Answer 40

[Cr(NH3)6]3+ purple solution

Question 41

Iron and iodide reaction

Answer 41

2Fe3+ + 2I- -->2Fe2+ + I2

Question 42

what does amore positive standard electrode potential mean in terms of a reaction

Answer 42

an equilibrium is more likely to gain electros, shift to the right and undergo reduction

Question 43

Cr2O7 colour

Answer 43

orange

Question 44

Cr2+ ion colour

Answer 44

pale blue

Question 45

What will the standard electrode potential value of a very strong reducing agent be

Answer 45

more negative than comparative values

Question 46

acidic and alkaline which is used for oxidation the other reduction

Answer 46

acidic for oxidation alkaline for reduction

Question 47

What is H2O2 used for with Cr3+

Answer 47

as an oxidising agent oxidises Cr3+ to CrO4 2-

Question 48

Reaction of copper and iodine

Answer 48

2Cu2+ + 4I- --> 2CuI + I2 note its CuI not CuI2

Question 49

Cu solid colour

Answer 49

brown

Question 50

type of reaction of Cu2O and H2SO4

Answer 50

disproportionation

Question 51

Reaction of Cu2O and H2SO4

Answer 51

Cu2O + H2SO4 --> Cu + CuSO4 + H2O

Question 52

what happens when ammonium ions are heated with hydroxide

Answer 52

forms ammonia and water

Question 53

test for ammonia

Answer 53

heat with hydroxide damp red ph paper will turn blue

Question 54

carbonate test

Answer 54

Add dilute nitric acid effervescence as CO2 produced

Question 55

Sulfate test

Answer 55

add barium ions white precipitate of BaSO4 would be produced

Question 56

Halide ion test

Answer 56

add AgNO3

Question 57

solubility of halide test precipitates in NH3

Answer 57

only AgCl is soluble in dilute NH3 both AgBr and AgI soluble in concentrated NH3 only

Question 58

Chromium atom electron configuration difference

Answer 58

not 3d4 4s2 3d5