Redox Reactions(General Knowledge > General Science ) Questions and answers for exam Preparation

Question 1. What type of reaction is the following? Zn(s) + 2Cu(NO3)2(aq) ---> 2Cu(s) + Zn(NO3)2(aq)

double displacement
single displacement
precipitation
neutralization

Explanation:-

Answer: Option B. -> single displacement

Question 2. What is oxidation number of H in CaH2?

+1
-1
0
+2

Explanation:-

Answer: Option B. -> -1

Question 3. What is oxidation number of Cr in Cr2O72-?

-2
+2
+6
+12

Explanation:-

Answer: Option C. -> +6

Question 4. Name the following ionic compound: Cs2S

cesium sulfide
cesium sulfate
cesium (II) sulfate
cesium (II) sulfide

Explanation:-

Answer: Option A. -> cesium sulfide

Question 5. Which problem is balanced?

PbO2 + 2H2
SO2 + H20 --> H2SO4
2Na + 2H2O --> 2NaOH + H2
all of the above

Explanation:-

Answer: Option C. -> 2Na + 2H2O --> 2NaOH + H2

Question 6. What will be the result of the following: Br2 + NaF ->

bromine will replace Na
Na will replace Br
Br will replace F
no reaction will occur

Explanation:-

Answer: Option D. -> no reaction will occur

Question 7. The statements which contain correct definitions of reduction

the removal of oxygen
the decrease in oxidation state/p>
the removal of electrons
Both A & B

Explanation:-

Answer: Option D. -> Both A & B

Question 8. A compound having +2 oxidation state of O is

H2O
H2O2
OF2
O2F2

Explanation:-

Answer: Option C. -> OF2

Question 9. Which of the following represents reduction?

C → CO
N2 → NH3
Zn → Zn2+
H2 → H2O

Explanation:-

Answer: Option B. -> N2 → NH3

Question 10. Which of the following represents oxidation?

C → CH4
Fe3+ → Fe2+
Cl2 → 2Cl-
Zn → ZnO

Explanation:-

Answer: Option D. -> Zn → ZnO