CBSE
Multiple Choice QuestionsWhich of the following elements shows +4 oxidation state?
Sn
Ra
Fr
Sc
Assertion : Chlorine undergoes disproportionation reaction in alkaline medium.
Reason : Cl2 is an oxidising agent.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false.
Among the following pairs of ions, the lower oxidation state in aqueous solution is more stable than the other, in
Tl+, Tl3+
Cu+, Cu2+
Cr2+, Cr3+
V2+, VO2+
Assertion : The formal oxidation no. of sulphur in Na2S4O6 is 2.5.
Reason : Two S-atoms are not directly linked with O-atoms.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
In the balanced chemical reaction
IO3- + aI- + bH+ → cH2O + dI2
a, b, c and d respectively corresponds to
5, 6, 3, 3
5, 3, 6, 3
3, 5, 3, 6
5, 6, 5, 5
The charge required for the reduction of 1 mol of to MnO2 is
1 F
2 F
3 F
6 F
When KMnO4 reacts with KBr in alkaline medium gives bromate ion. Then oxidation state of Mn changes from +7 to
+6
+4
+3
+2
The oxidation number of carbon in CH2O is :
- 2
+ 2
0
+ 4
Which of the following reaction involves oxidation and reduction ?
NaBr + HCl NaCl + HBr
HBr + AgNO3 AgBr + HNO3
H2 + Br2 2HBr
Na2O + H2SO4 Na2SO4 + H2O
The correct order of stability of the superoxides is
KO2 > RbO2 > CsO2
KO2 > CsO2 > RbO2
CsO2 > RbO2 > KO2
RbO2 > CsO2 > KO2
