transition elements

Question 1

what is the electronic configuration of Cu

Answer 1

1S2 2S2 2P6 3S2 3P6 4S1 3D10

Question 2

what is the electronic configuration of Cr

Answer 2

1S2 2S2 2P6 3S2 3P6 4S1 3D5

Question 3

What is the rule when determining the electronic configuration of a transition metal ion

Answer 3

electrons are lost from the 4s before the 3d when d-block elements form ions.

Question 4

define transition elements

Answer 4

d-block elements that form one or more stable ion with a partially filled d-subshell.

Question 5

what are the three properties of transition metals

Answer 5

can exist in more than one oxidation state
form coloured ions
possess catalytic behaviour

Question 6

define a complex ion

Answer 6

a transition element ion surrounded by ligands

Question 7

define a ligand

Answer 7

species that donates a pair of electrons to a transition metal ion to form a co-ordinate bond

Question 8

define a co-ordination number

Answer 8

the total number of co-ordinate bonds being made to a transition element ion

Question 9

define a monodentate ligand

Answer 9

donates one lone pair of electrons to form one co-ordinate bond

Question 10

define a bidentate ligand

Answer 10

donates two pairs of electrons to a transition metal ion to form two co-ordinate bonds

Question 11

what is the bond angle on square planar

Answer 11

90

Question 12

define an optical isomer

Answer 12

non-super imposable mirror image

Question 13

what is the test for transition elements

Answer 13

NaOH (precipitation reaction) or react with NH3 which produces OH- in solution

Question 14

what is the colour of the solution before NaOH is added, and the colour of the precipitate after NaOH has been added?

Cu2+ + 2OH- —-> Cu(OH)2 (s)

Answer 14

solution - blue
precipitate - blue

Question 15

what is the colour of the solution before NaOH is added, and the colour of the precipitate after NaOH has been added?

Fe2+ + 2OH- —-> Fe(OH)2 (s)

Answer 15

solution - pale green
precipitate - green

Question 16

what is the colour of the solution before NaOH is added, and the colour of the precipitate after NaOH has been added?

Fe3+ +3OH- ——> Fe(OH)3 (s)

Answer 16

solution - yellow
precipitate - orange/brown

Question 17

what is the colour of the solution before NaOH is added, and the colour of the precipitate after NaOH has been added?

Mn2+ + 2OH- —–> Mn(OH)2 (s)

Answer 17

solution - pale pink
precipitate - pale brown

Question 18

what is the colour of the solution before NaOH is added, and the colour of the precipitate after NaOH has been added?

Cr3+ + 3OH- —>Cr(OH)3 (s)

what is the colour produced when excess NaOH is added

Answer 18

solution - violet
precipitate - grey-green

excess - dark green solution [cr(OH)6] 3-

Question 19

what is the colour change that occurs when excess NH3 is added to [Cu(H2O)6] 2+

Answer 19

blue solution —> deep blue solution

Question 20

what is the colour change when excess NH3 is added to [Cr(h2O)6]

Answer 20

violet solution —-> purple solution

Question 21

what is the colour change that occurs when [Cu(h2O)6] reacts with chlorine ions in a ligand substiution reaction

Answer 21

blue solution —-> yellow solution

Question 22

haemoglobin is an octahedral complex with an Fe 2+ at the centre, what is the name of the complex when O2 is bound

Answer 22

oxyhaemoglobin (HbO)

Question 23

haemoglobin is an octahedral complex with an Fe 2+ at the centre, what is the name of the complex when CO is bound

Answer 23

carboxyhaemoglobin (HbCO)

Question 24

why is CO deadly

Answer 24

CO binds irreversibly to haemoglobin to form HbCO, which prevents the transport of O2 around the body

Question 25

what is cis-platin used for

Answer 25

binds to DNA to prevent cell division and so is used in the treatment of cancer