ions in aqueous solution

Question 1

Observation and formula for iron II with NaOH

Answer 1

Green sol to green ppt that turns brown standing in air
[Fe(H2O)6]2+ +2OH- > Fe(H2O)4(OH)2 (s) + 2H2O

Question 2

Observation and formula of copper II with NaOH

Answer 2

Blue sol to blue ppt
[Cu(H2O)6]2 ~+ 2OH- > Cu(H2O)4(OH)2 (s) + 2H2O

Question 3

Observation and formula of iron III with NaOH

Answer 3

Brown solution to brown ppt
[Fe(H2O)6]3+ + 3OH- > Fe(H2O)3(OH)3 (s) +3H2O

Question 4

Observation and formula of aluminum III with NaOH

Answer 4

Colourless sol to white ppt
[Al(H2O)6]3+ +3OH- > Al(H2O)3(OH)3 (s) #+ 3H2O

Question 5

Action of excess NaOH on iron II, copper II and iron II

Answer 5

No further change

Question 6

Formula and observation of Aluminum III with excess NaOH

Answer 6

Colourless sol to white ppt to colourless sol
Al(OH)₃(H₂O)₃ + OH- (aq) > [Al(OH)4(h2O)2]^- (aq) + H2O

Question 7

What happens when a white ppt of Al(OH)₃(H₂O)₃ reacts with acid

Answer 7

Al(OH)₃(H₂O)₃ + 3H+ (aq) > [Al(H2O)6]3+(aq)
colourless solution is formed

Question 8

why can aluminium salt act as an acid or a base

Answer 8

-amphoteric
-so if NaOH is in excess the salt acts as an acid and is hydrolysed further

Question 9

Observation and formula for iron II with NH3

Answer 9

Green sol to green ppt that goes brown standing on air
[Fe(H2O)6]2+ 2NH3 > Fe(H2O)4(OH)2 (s) + 2NH4+

Question 10

Observation and formula for Copper II with NH3

Answer 10

Blue sol to blue ppt

[Cu(H2O)6]2+ + 2NH3 > Cu(H2O)4(OH)2 (s)+2NH4+

Question 11

Observation and formula for iron III with NH3

Answer 11

Purple sol to orange - brown ppt

[Fe(H2O)6]3+ + 3NH3 > Fe(H2O)3(OH)3 (s) +3NH4+

Question 12

Observation and formula for Aluminum III with NH3

Answer 12

Colourless sol to white ppt

[Al(H2O)6]3+ +3NH3 > Al(H2O)3(OH)3 (s) + 3NH4+

Question 13

Action of excess NH3 on iron II, Iron III and aluminium III

Answer 13

No further change

Question 14

Observation and formula of excess NH3 on copper II

Answer 14

Blue sol to royal blue sol

[Cu(H2O)4(OH)2] + 4NH3 > [Cu(H2O)2(NH3)4]^2+ + 2H2O =2OH-

Question 15

Observation and formula of iron II on Na2CO3

Answer 15

Green sol to green ppt
[Fe(H2O)6]2+ + CO32- > FeCO3 +6H2O

Question 16

Observation and formula of copper II on Na2CO3

Answer 16

Blue sol to blue-green ppt
[Cu(H2O)6]2+ + + CO32- >CuCO3 (s) +6H2O

Question 17

Reactions with Na2CO3 copper II and iron II

Answer 17

solutions of these metal 2+ ions react with sodium carbonate as acids to form insoluble carbonates and water

Question 18

Observation and formula of iron III on Na2CO3

Answer 18

Purple sol to orange-brown ppt AND CO2
2[Fe(H2O)6]3+ + 3CO32- > 2Fe(H20)3(OH)3 + 3H2O + 3CO2

Question 19

Observation and formula of aluminium III with Na2CO3

Answer 19

Colourless sol to white ppt + CO2

2[Al(H2O)6]3+ + 3CO32-> Al(H2O)3(OH)3 (s) + 3H2O +3CO2

Question 20

reactions with Na2CO3 iron III and Al III

Answer 20

solutions of these metal 3+ ions act as a stronger acid so react with sodium carbonateto form salt and water

Question 21

Observation and formula for iron II with Cl-

Answer 21

[Fe(H2O)6]2+ +4Cl- > [FeCl4]2- + 6H2O

Question 22

Observation and formula for copper II with Cl-

Answer 22

[Cu(H2O)6]2+ +4Cl- > [CuCl4]2- + 6H2O

Question 23

Observation and formula for iron II with Cl-

Answer 23

[Fe(H2O)6]3+ +4Cl- > [FeCl4]- + 6H2O

Question 24

Observation and formula for aluminium III with Cl-

Answer 24

Al(H2O)6]3+ +4Cl- > [AlCl4]- + 6H2O