Transition metals

Question 1

define the term transition metal

Answer 1

one that forms atleast one stable ion with a partially filled d-subshell

Question 2

Why is scandium not a transition metal

Answer 2

Sc3+ only ion and d-subshell is empty

Question 3

Why is scandium not a transition metal

Answer 3

Sc3+ only ion and d-subshell is empty

Question 4

what are the characteristics of transition metals

Answer 4

• complex ions
• variable oxidation states
• coloured ions
• catalytic properties

Question 5

What is a ligand

Answer 5

molecule or ion that forms a co-ordinate bond w a transition metal by donating a pair of electrons

Question 6

what is a complex ion

Answer 6

metal ion surrounded by ligands

Question 7

Name 2 bidentate ligands

Answer 7

• ethane-1,2-diamine ( NH2CH2CH2NH2 )
• ethanedioate ion ( C2O4 2- )

Question 8

shape for [Cu(H2O)6]2+

Answer 8

octahedral

Question 9

shape for [CoCl4]2-

Answer 9

Tetrahedral

Question 10

shape for [Pt(NH3)2(Cl)2]

Answer 10

Square planar

Question 11

shape for [Ag(NH3)2]+

Answer 11

Linear ( oxidised w tollens reagent )

Question 12

Why do chloro complexes tend to tetrahedral

Answer 12

too big to fit anymore than 4 Cl- ligands around the metal ion

Question 13

Describe the chelate effect in this reaction
[Cu(H2O)6]2+ + 3 H2NCH2CH2NH2 <-> [Cu(DiAmine)3]2+ + 6 H2O

Answer 13

• 4 molecules on the left to 7 on the right
• large increase in entropy ( thermodynamically favourable )

Question 14

why is CO toxic in haemoglobin

Answer 14

• replaces O2 co-ordinately bonded to Fe(II) in haemoglobin bond

Question 15

bond angle in Trans isomer

Answer 15

180

Question 16

bond angle in Cis isomer

Answer 16

90

Question 17

What is cisplatin

Answer 17

• effective anti-cancer drug
• binds to DNA in cancer cells stopping cell replication
• Two Cl- ions subbed for two N atoms on adjacent guanine bases

Question 18

In a pure transition metal atom all d-orbitals are of equal energy. This is known a

Answer 18

ground state

Question 19

in TM the presence of other atoms causes

Answer 19

the d-orbitals to have slightly different energies enables electrons to be excited from one d orbital to another.

Question 20

When an electron moves from a lower energy d orbital to a higher energy d orbital (called the excited state) the energy needed to make the transition is taken from

Answer 20

white light.

Question 21

why are chloride ions sometimes considered to not be ligands

Answer 21

too big