Redox Reactions

Redox Reactions
Class:XI / Unit:8

1. Which of the compounds can exist together?

FeCl₃, KI
FeCl₂, SnCl₂
HgCl₂, SnCl₂
FeCl₃, SnCl₂

2. Find the redox reaction

In the atmosphere, O₃ from O₂ by lighting
Evaporation of water
Both oxidation and reduction reaction
The reaction of H₂SO₄ with NaOH

3. Which among the following compounds is the most reducing compound?

H₂S
H₂SO₃
HNO₂
SnCl₂

4. Which among the following is the strongest oxidising agent?

K₂Cr₂O₇
KMnO₄
H₂O₂
O₃

5. Which of the following represents a redox reaction?

BaCl₂ + H₂SO₄ → BaSO₄ + 2HCl
NaOH + HCl → NaCl + H₂O
CuSO₄ + 2H2O → Cu(OH)₂ + H₂SO₃
Zn + 2HCl → ZnCl₂ + H₂

6. Zn gives H₂ gas with H₂SO₄ and HCl but not with HNO₃ because

In electrochemical series, Zn is above hydrogen
Zn acts as an oxidising agent when it reacts with HNO₃
HNO₂ is a weaker acid than H₂SO₄ and HCl
NO₃^– is reduced in preference to hydronium ion

7. In the Reaction
3Br₂ + 6CO₃^–2 + 3H₂O → 5Br^– + BrO₃^– + 6HCO₃^–

bromine is neither reduced nor oxidised
bromine is both reduced and oxidised
bromine is oxidised and carbonate is reduced
bromine is reduced and water is oxidised

8. Oxidation number of Cl in CaOCl₂

-1
+1
+1 & -1
0

9. Which of the following substances acts as ah oxidising as well as reducing agent?

NaN0₂
Daltons Atomic Theory
Na₂0₂
Na₂0

10. Whenever a reaction between an oxidising agent and a reducing agent is carried out

a compound of lower oxidation state is formed if the reducing agent is in excess
a compound of higher oxidation state is formed if the oxidising agent is in excess
Both (a) and (b)
None of the above