Metal Aqua Ions (II)

Question 1

Reactions of copper (II), iron (II), iron (III) and aluminium (III) aqua ions with Sodium Hydroxide

Exception and explain

Answer 1

All four metal aqua ions will form precipitates with NaOH.

Only the aluminium hydroxide precipitate will dissolve in an excess of NaOH as it’s amphoteric

Question 2

Reactions of copper (II), iron (II), iron (III) and aluminium (III) aqua ions with Ammonia

Exception and explain

Answer 2

All four metal aqua ions will form precipitates with ammonia.

Only the copper hydroxide precipitate will dissolve in an excess of ammonia.

This is because it undergoes a ligand exchange reaction with excess ammonia

Question 3

Reactions of copper (II), iron (II), iron (III) and aluminium (III) aqua ions with Sodium Carbonate

Solutions containing Al3+ or Fe3+

Answer 3

All four metal aqua ions will form precipitates with sodium carbonate.

Also form bubbles as CO2 is formed

Question 4

Colour of (Cu (H2O)6)2+ with OH- or NH3

Answer 4

Blue precipitate

Question 5

Colour of (Cu (H2O)6)2+ with excess OH-

Answer 5

No colour change (ie blue solution)

Question 6

Colour of (Cu (H2O)6)2+ with excess NH3

Answer 6

Deep blue solution

Question 7

Colour of (Cu (H2O)6)2+ with Na2CO3

Answer 7

Green-blue precipitate

Question 8

Colour of (Fe (H2O)6)2+ with OH- or NH3

Answer 8

Green precipitate

Question 9

Colour of (Fe (H2O)6)2+ with excess OH-

Answer 9

No colour change (ie green solution)

Question 10

Colour of (Fe (H2O)6)2+ with excess NH3

Answer 10

No colour change (ie green solution)

Question 11

Colour of (Fe (H2O)6)2+ with Na2CO3

Answer 11

Green precipitate

Question 12

Colour of (Al (H2O)6) 3+ with OH- or NH3

Answer 12

White precipitate

Question 13

Colour of (Al (H2O)6) 3+ with excess OH-

Answer 13

Colourless solution

Question 14

Colour of (Al (H2O)6) 3+ with excess NH3

Answer 14

No change (ie colourless solution)

Question 15

Colour of (Al (H2O)6) 3+ with Na2CO3

Answer 15

White precipitate

Question 16

Colour of (Fe (H2O)6) 3+ with OH- or NH3

Answer 16

Brown precipitate

Question 17

Colour of (Fe (H2O)6) 3+ with excess OH-

Answer 17

No change (ie yellow solution)

Question 18

Colour of (Fe (H2O)6) 3+ with excess NH3

Answer 18

No change (ie yellow solution)

Question 19

Colour of (Fe (H2O)6) 3+ with Na2CO3

Answer 19

Brown precipitate

Question 20

Colour of solution of (Cu (H2O)6) 2+ metal aqua ion

Answer 20

Blue solution

Question 21

Colour of solution of (Fe (H2O)6) 2+ metal aqua ion

Answer 21

Green solution

Question 22

Colour of solution of (Al (H2O)6) 3+ metal aqua ion

Answer 22

Colourless solution

Question 23

Colour of solution of (Fe (H2O)6) 3+ metal aqua ion

Answer 23

Yellow solution