Transitional Metals

Question 1

What is a ligand?

Answer 1

A molecule or ion that forms a co-ordinate bond with a transitional metal by donating a pair of electrons

must have a lone pair

Question 2

What is a complex ion?

Answer 2

central metal atom or ion surrounded by ligands

Question 3

What’s significant about Cl- ion compared to NH3 and H2O

Answer 3

They have a large size

Question 4

What are the 4 characteristics of transitional metal?

Answer 4

• complex formation
• formation of coloured ions
• variable oxidation state
• catalytic activity

Question 5

Why Zn is not a transitional metal?

Answer 5

Zn2+ only forms so this means that there is complete d-orbitual hence not transitional metal

Question 6

What is a bidentate ligand?

Answer 6

2 atoms with lone pairs and can form two coordinate bonds per ligand

Question 7

Example of multidentate ligand

Answer 7

EDTA+

Question 8

Explain the process of Haemoglobin and the effect of CO.

Answer 8

*Oxygen forms a co-ordinate bond to Fe(II) in haemoglobin
*This enables oxygen to be transported in the blood
—————
*CO is toxic because it forms a strong coordinate bond with haemoglobin and it replaces the oxygen

Question 9

Equation to show formation of multidentate complexes from [Cu(H2O)6]2+

Answer 9

[Cu(H2O)6]2+ +EDTA4- —> [Cu(EDTA)]2- +6H2O

Question 10

How do these metals present colour?

Answer 10

white light gets absorbed and electrons gets excited and only the colour lights gets reflected

Question 11

Colours occur when the electron configuration has?

Answer 11

partially, filled d-orbitual

Question 12

What kind of bonds are held in complex ion?

Answer 12

Dative Covalent bond

Question 13

Charge of NH3, H2O

Answer 13

0

Question 14

Octahedral has what kind of arrows and how many?

Answer 14

2 wedges, 2 dashes, 2 normal bond

Question 15

What kind of transitional metals would be square planar? (sometimes)

Answer 15

Nickel, Platinum, Palladium

Question 16

What kind of shape do Cl- tend be?

Answer 16

Tetrahedral (no matter what)

Question 17

Cis and Trans means? use for inorganic

Answer 17

Cis (same)
trans (opposite)

Question 18

In octahedral, if chlorine next to each other (90 degrees) then is it cis/trans

What makes it trans?

Answer 18

cis
if the chlorine is physically opposite to each other

Question 19

Ions with higher oxidation state, absorb higher… ( but cant tell about a colour :( )

Answer 19

frequencies of light

Question 20

3 ways in which a metal complex can be changed to alter its colour

Answer 20

ligand substitution
oxidation sate
coordination number

Question 21

different ligands causes different…

Answer 21

d-orbitual splitting

Question 22

what bidentate ligand is NH2-CH2-CH2-NH2? and what’s their charge

Answer 22

-en-
H2N-CH2-CH2-NH2
0 charge

Question 23

What other examples of bidentate ligand

Answer 23

ethanedioate ( C with 2 double bond O and 2 bond with O- lone pair )

Question 24

Why does a reaction proceeds in relations to chelate effect?

Answer 24

There are more particles on products than reactants
This increases entropy so it will be positive
As T always positive, Gibbs will be negative so reaction is feasible

Question 25

what’s the charge of EDTA

Answer 25

4-

Question 26

What is a heterogenous catalyst?

Answer 26

different phase from reactants

Question 27

How to increase the number of active sites? Heterogenous only**

Answer 27

by increasing surface area,
a) making the catalyst: in ^powder
b) as a ^coating on a support medium

Question 28

What is the 2 equations of the Contact process? Heterogeneous Catalyst

Answer 28

1) SO2 (g) + V2O5 (s) —-> SO3 (g) +V2O4 (s)
2) V2O4 (s) + 1/2 O2 (g) —> V2O5 (s)

Question 29

How does the contact process lead to the creation of sulfuric acid?

Answer 29

SO3 (g) +H2O (l) —> H2SO3 (aq)

Question 30

How does catalyst poisoning occur?

Answer 30

Impurities bind to a catalyst’s active sites and prevent it from functioning

Question 31

How Fe2+ ions catalyse reaction between S2O8 2- and I-?

Answer 31

*Fe2+ ions and S2O8 2- ions attract as they have opposite charges
*Similarly with I-
*This means that activation energy decreases as before
*Iron’s variable oxidation state allows to react either reactants

Question 32

What is the 2 equation of the contact process? Homogeneous catalyst

Answer 32

1) 1/2 S2O8 2- (aq) + Fe2+ (aq) –> SO4 2- (aq) +Fe3+ (aq)
2) Fe3+ (aq) +I- (aq) –> Fe2+ (aq) +1/2 I2 (aq)

Question 33

Explain the process of autocatalyst graph?

Answer 33

1. Initially, the reactants are same charge so repel hence the reaction is slow
2. it produces Mn2+, the catalyst increases the rate of reaction
3. As the reactants gets used up, the rate decreases

Question 34

What is the equation of autocatalyst? + overall

Answer 34

1) 4Mn2+ + MnO4- +8H+ —> 5Mn3+ +4H2O
2) 2Mn3+ + C2O4 2- —> 2Mn2+ +2CO2

• 2MnO4- +16H+ +5C2O4 2- —> 2Mn2+ + 10CO2 + 8H2O

Question 35

What are all the colours of these metal-aqua ions? Fe2+, Fe3+, Cu2+ and Al3+

Answer 35

+(H2O)6
Fe2+ green solution
Fe3+ yellow solution
Cu2+ blue solution
Al3+ colourless

Question 36

Which one will be a stronger acid x 2+ or x 3+ and why?

Answer 36

3+. A higher charge so greater attraction of electron and have smaller radius. higher charge/size ratio

Question 37

What equation is when Ethane-1,2-diamine reacts with [Co(H2O)6] 2+

Answer 37

[Co (H2O)6]2+ + 3NH2CH2CH2NH2 →
[Co(NH2CH2CH2NH2)3]2+ +6H2O

Question 38

Why same charged ions are very slow at start?

Answer 38

→ no catalyst start
→ same charge, repels
→ activation energy is high