What enables HNO₂ to act as both a reducing and an oxidizing agent, in contrast to HNO₃ which only acts as an oxidizing agent?

1. Hybridization of N-atom in HNO₂

2. Maximum oxidation state of N - atom in HNO₂

3. Lower oxidation state of N-atom in HNO₂

4. Higher Electronegativity of N -atom in HNO₃

A brown ring complex compound is formulated as $\left[Fe{\left(H_{2}O\right)}_{5}NO\right]S{O}_4.$ The oxidation state of iron is 

1. 1

2. 2

3. 3

4. 0

What is the oxidation number of Co in $\left[Co{\left(N{H}_3\right)}_{4}ClN{O}_2\right]$

(1) + 2

(2) + 3

(3) + 4

(4) + 5

The equivalent weight of phosphoric acid (H₃PO₄) in the reaction $NaOH+H_{3}P{O}_4\to Na{H}_{2}P{O}_4+H_{2}O$ is

(1) 25

(2) 49

(3) 59

(4) 98

Oxidation number of oxygen in potassium super oxide (KO₂) is:

1. – 2

2. – 1

3. – 1/2

4. – 1/4

The pair of compounds that can exist together is

1. FeCl₃, SnCl₂             

2. HgCl₂, SnCl₂

3. FeCl₂, SnCl₂             

4. FeCl₃, KI

An excess of NaOH was added to 100 mL of a ferric chloride solution. This caused the precipitation of 1.425 g of Fe(OH)₃. Calculate the normality of the ferric chloride solution

(1) 0.20 N

(2) 0.50 N

(3) 0.25 N

(4) 0.40 N

Equivalent weight of a metal oxide is 20, the equivalent weight of sulphate of same metal will be 

(1) 60

(2) 69

(3) 108

(4) 54

What is the equivalent weight of H₃PO₃ in the following disproportionation reaction:-

H₃PO₃ $\to$H₃PO₄ + PH₃

1. $\frac{M}{6}$   

 2. $\frac{M}{2}$ 

3.  $\frac{2M}{3}$ 

 4. $\frac{M}{3}$

N₂H₄ + IO₃^- + 2H⁺ + Cl^- $\to$ICl + N₂ + 3H₂O

The equivalent masses of N₂H₄ and KIO₃ respectively are :-

1. 8 and 35.6

2. 8 and 87

3. 8 and 53.5

4. 16 and 53.5