Module 5, Section 3

Question 1

What is the colour of MnO4-?

+7

Answer 1

Purple

Question 2

What is the colour of Cr2O72-?

+6

Answer 2

Orange

Question 3

What is the colour of MnO42-?

+6

Answer 3

Green

Question 4

What is the colour of VO2+?

+5

Answer 4

Yellow

Question 5

What is the colour of VO2+?

+4

Answer 5

Blue

Question 6

What is the colour of Ti3+?

+3

Answer 6

Purple

Question 7

What is the colour of V3+?

+3

Answer 7

Green

Question 8

What is the colour of Cr3+?

+3

Answer 8

Green

Question 9

What is the colour of Fe3+?

+3

Answer 9

Yellow

Question 10

What is the colour of Ti2+?

+2

Answer 10

Violet

Question 11

What is the colour of Ni2+?

+2

Answer 11

Green

Question 12

What is the colour of V2+?

+2

Answer 12

Violet

Question 13

What is the colour of Mn2+?

+2

Answer 13

Pale pink

Question 14

What is the colour of Fe2+?

+2

Answer 14

Pale green

Question 15

What is the colour of Co2+?

+2

Answer 15

Pink

Question 16

What is the colour of Cu2+?

+2

Answer 16

Pale blue

Question 17

In which reaction does CuSo4 act as a catalyst?

Answer 17

Zn + H2SO4 = ZnSO4 + H2

Question 18

In which reaction does MnO2 act as a catalyst?

Answer 18

2H2O2 = 2H2O + O2

Question 19

In which reaction does Fe act as a catalyst?

Answer 19

N2 + 3H2 = 2NH3

Question 20

What colour is a copper(II) hydroxide precipitate?

Answer 20

It goes from a pale blue solution to a blue precipitate.

Question 20

What colour does a copper(II) solution go when reacted with excess NH3?

Answer 20

Dark blue

Question 20

What colour is an iron(II) hydroxide precipitate?

Answer 20

It goes from a pale green solution to a green precipitate.

Question 21

What colour is an iron(III) hydroxide precipitate?

Answer 21

It goes from a yellow solution to an orange precipitate.

Question 22

What colour is a manganese(II) hydroxide precipitate?

Answer 22

It goes from a pale pink solution to a pink/buff precipitate.

Question 23

What colour is a chromium(III) hydroxide precipitate?

Answer 23

This goes from a green solution to a grey-green precipitate.

Question 24

What colour does a chromium(III) solution go when reacted with excess NaOH?

Answer 24

Dark green

Question 25

What colour does a chromium(III) solution go when reacted with excess NH3?

Answer 25

Purple colour

Question 26

What is the colour of [Cr(H2O)6]3+?

Answer 26

Violet

Question 27

What is the colour of [Cr(NH3)6]3+?

Answer 27

Purple

Question 28

What is the colour of [CuCl4]2-?

Answer 28

Yellow

Question 29

What colour is a precipitate of Cu2+ when NaOH solution is added?

Answer 29

Blue

Question 30

What colour is a precipitate of Fe2+?

Answer 30

Green

Question 31

What colour is a precipitate of Fe3+?

Answer 31

Orange

Question 32

What colour is a precipitate of Mn2+?

Answer 32

Pink/buff

Question 33

What colour is a precipitate of Cr3+?

Answer 33

Grey-green

Question 34

In which reaction does V2O5 act as a catalyst?

Answer 34

2SO2 + O2 = 2SO3

Question 35

When is nickel used as a catalyst?

Answer 35

In the hydrogenation of vegetable fats in the manufacture of margarine.