practical

Question 1

Observation for ligand replacement for hexaaquacopper ions

Answer 1

With ammonia solution - Blue precipitate forms. Excess ammonia dark blue solution forms

With concentrated HCl - blue solution changes to yellow

Question 2

Recall the aqueous complexes of the following

Cr3+

Answer 2

Green

Question 3

Cr2O7 2-

Answer 3

Orange

Question 4

CrO4 2-

Answer 4

Yellow

Question 5

Mn 2+

Answer 5

Pink

Question 6

Fe 2+

Answer 6

Green

Question 7

Fe 3+

Answer 7

Orage

Question 8

Co 2+

Answer 8

Pink

Question 9

Ni2+

Answer 9

Green

Question 10

Cu 2+

Answer 10

Blue

Question 11

V 2+

Answer 11

Violet

Question 12

V3+

Answer 12

Green

Question 13

VO2+

Answer 13

Bue

Question 14

VO2 +

Answer 14

Yellow

Question 15

For the following give the colour of the complex and if its soluble in excess sodium hydroxide or excess ammonia
Cr3+

Answer 15

Green-blue precipitate soluble in excess sodium hydroxide

Question 16

Mn2+

Answer 16

White ppt , turns brown on standing, insoluble

Question 17

Fe2+

Answer 17

Green ppt, insoluble

Question 18

Fe3+

Answer 18

Brown ppt, insoluble

Question 19

Co2+

Answer 19

Blue ppt, soluble in excess ammonia, yellow solution

Question 20

Ni2+

Answer 20

Green ppt, soluble in excess ammonia, blue solution

Question 21

Cu2+

Answer 21

Blue ppt, soluble in excess ammonia dark blue solution

Question 22

What is observed in the reaction of amino acids with copper (II) sulfate?

Answer 22

Solution turns blue black

Question 23

What is the appearance of aspirin?

Answer 23

White crystals.