Redox Reaction Test

Result

Redox Reaction Test - 9

Score
-
out of -
Rank
-
out of -

TIME Taken - -

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Weekly Quiz Competition

Question 1
1 / -0

Direction (Q. Nos. 1-18) This section contains 18 multiple choice questions. Each question has four
choices (a), (b), (c) and (d), out of which ONLY ONE option is correct.
Q. Oxidation can be defined as the terms
I. gain of electron and hydrogen
II. gain of oxygen and loss of electron
III. increase in oxidation number
IV. decrease in oxidation number
Select the correct terms

A
I and II

B
II and III

C
I and III

D
I and IV

Solution

Oxidation number increases, oxygen gained and loss of electrons is oxidation.
Question 2
1 / -0

Reduction is defined in terms of
I. electronation and hydrogenation
II. deelectronation and gain of oxygen
III. increase in oxidation number
IV. decrease in oxidation number
Select the correct terms

A
I and IV

B
I and III

C
II and II

D
I and II

Solution

Gain of hydrogen , electron and decrease in oxidation number is reduction
Question 3
1 / -0

In balancing the half-reaction, CN^-→ CNO^-
The number of electrons that must be added is

A
0

B
4 on ther ight

C
4 on the left

D
2 on the right

Solution

CN^-→ CNO^-
4+ x = -1 4+ x-2 = -1
∴ x = -5 ∴ x = -3
Oxidation number increases. This is oxidation.
CN^-→ CNO^-+ 2e^-
Question 4
1 / -0

Select the set of compounds with oxidation-reduction duality.

A
Cl₂, H₃PO₄, HCHO, HNO₂

B
Cl₂, H₃PO₃, C₆H₅CHO, H₂O₂

C
Br₂, H₃PO₂, CH₃CHO, H₃PO₄

D
CrO₂Cl₂, KMnO₄, SO₃, CO₂

Solution

Com pounds having oxidising and reducing nature in given reaction are said to have oxidation-reduction duality. Such compounds are said to undergo disproportionation reaction.

(This is called Cannizzaro reaction.)

Note Such compounds have O.N. of the affected atoms intermediate of oxidation part and reduction part
Question 5
1 / -0

In the following balanced reaction,

A
x = - 1 and species is superoxide

B
x = - 2 and species is peroxide

C
x = 0 and species is oxygen

D
x = - 4 and species is oxide

Solution

If balanced, then to balance charge
x = - 1
Question 6
1 / -0

I⁻ reduces IO₃^- and I₂ and itself oxidised to I₂ in acidic medium. Thus, final reaction is

A

B

C

D
None of the above is correct

Solution

To balance oxidation number, cross-multiply by change in oxidation number
Question 7
1 / -0

H₂O can be oxidised to

A
H₂ and O₂

B
O^2-

C
OH^-

D
O₂

Solution

H is reduced to H₂ and O is oxidised to O₂.
Question 8
1 / -0

Consider the following reactions,
I. Zn + dil. H₂SO₄ → ZnSO₄ + H₂
II. Zn + conc. H₂SO₄ → ZnSO₄+ SO₂ + H₂O

Oxidising agents in I and II are

A
a

B
b

C
c

D
d

Solution
Question 9
1 / -0

In the following reactions except in one, oxygen is the reducing agent. Exceptional reaction is

A
2 Ag₂O → 4Ag + O₂

B
4NH₃+ 3O₂ → 2N₂ + 6H₂O

C
2F₂ + 2H₂O → 4HF + O₂

D
2AgNO₃ + H₂O₂ → 2AG + 2HNO₃ + O₂

Solution

Ag⁺ is reduced to Ag by oxygen

Thus, except in (b), oxygen behaves as reducing agent.
Question 10
1 / -0

In the following reaction,
Which ions are not balanced?

A
I^-, I₂

B

C
H⁺, H₂O

D
None of them are balanced

Solution

To balance electron (II) is to be multiplied by (3). Thus,
Question 11
1 / -0

Coefficient x, y and z are respectively

A
a

B
b

C
c

D
d

Solution

Cross -multiply by change in oxidation number and balance H by H⁺ ions.

Thus, x = 2, y = 5 and z = 6
Question 12
1 / -0

Which of the following species does not show disproportionation reaction?

A

B

C

D

Solution

Maximum oxidation number of Cl = + 7

Thus, species with + 7 oxidation number can be reduced but not oxidised.
Question 13
1 / -0

Which is the intramolecular oxidation-reduction reaction?

A

B

C

D
All of the above

Solution
Question 14
1 / -0

Consider the following experimental facts,
I. When Cl₂ gas is passed into Kl solution containing CHCI₃, violet colour appears in CHCI₃ layer.
II. When Cl₂ gas is passed into KBr solution containing CHCI₃, orange colour appears in CHCI₃ layer.
III. When Cl₂ gas is passed into a solution containing KBr, Kl and KCI, containing CHCI₃, violet colour appears in CHCI₃ layer.
Select the correct experimental facts.

A
I and II

B
I and III

C
III Only

D
II and III

Solution

Oxidising power of F₂ > CI₂ > Br₂ > l₂

Thus, (II) is true.

In experiment (III), orange colour of Br₂ does not appear, as it also oxidises Kl to l₂. Hence , only violet colour appears in CHCI₃ layer. Thus, (III) is also true.
Question 15
1 / -0

Based on the following reaction,
It can be concluded that

A

B

C
it is a disproportionation reaction

D
it is not a redox reaction

Solution

Since, ΔG ° < 0, hence it is spontaneous in forward direction . Oxidation number of Xe decreases hence, it is an oxidising agent and oxidation number of F increases, hence it is a reducing agent.
Question 16
1 / -0

For the redox reaction,

x, y and z are

A
a

B
b

C
c

D
d

Solution

To balance a redox reaction , balance effected atoms

II. Take oxidation number of two Cr-atom

Take total (oxidation number) of each atom (oxidised, re duced ) cross - multiply by change in oxidation number and add
I x 6 + II x 1

Thus, x = 6
y = 1
z = 14
Question 17
1 / -0

In the following conversion of chromite into soluble chromium salt
4Fe(CrO₂)₂+ 8Na₂CO₃ + 7O₂--> 2Fe₂O₃ + 8Na₂CrO₄ + 8CO₂
There is

A
oxidation of Fe and reduction of Cr

B
oxidation of Fe and Cr both and reduction of O

C
oxidation of Fe and Cr both and reduction of carbon

D
No redox reaction

Solution

Fe 2⁺ and Cr³⁺ are oxidised (increase in oxidation number)
O₂, is reduced .
Question 18
1 / -0

In which of the following reactions H₂O₂ acts as a reducing agent?

A
I and II

B
Ill and IV

C
I and III

D
II and IV

Solution

A species which is oxidised (deelectronation) is a reducing agent.

Thus, (ii) and (iv) represent reducing behaviour of H₂O₂.