Chemistry - Oxidation and Reduction
Exam Duration: 45 Mins Total Questions : 30
In the given reaction \(2Fe{ Cl }_{ 3 }+Sn{ Cl }_{ 2 }\longrightarrow 2Fe{ Cl }_{ 2 }+Sn{ Cl }_{ 4 }\) the substance which is reduced is
- (a)
Sn2+
- (b)
Fe3+
- (c)
Fe2+
- (d)
Sn4+
In oxygen difluoride the oxidation number of oxygen is
- (a)
-2
- (b)
-1
- (c)
+2
- (d)
+1
The oxidation number of hydrogen in calcium hydride is
- (a)
+1
- (b)
-1
- (c)
+2
- (d)
+2
The oxidation state of the two nitrogen in NH4 NO3 is
- (a)
+ 2 and + 3
- (b)
+ 5 and + 5
- (c)
+1.5 and 2.5
- (d)
0.5 and 1.5
Equal volumes each of 1M solution containing FeCl3 and SnCl2 are mixed together, the resultant solution will contain
- (a)
Fe2+, Sn2+, Sn4+
- (b)
Fe2+, Fe3+, Sn2+
- (c)
Fe2+, Fe3+, Sn4+
- (d)
Sn2+, Sn4+, Fe3+
In which one of the following the oxidation number of sulphur is zero?
- (a)
H2SO3
- (b)
H2SO4
- (c)
H2SO5
- (d)
(CH3)2SO
In a redox reaction
- (a)
oxidant gets reduced
- (b)
oxidant loses electrons
- (c)
reductant gets reduced
- (d)
reductant gains electrons
In the reaction \({ I }_{ 2 }+2{ S }_{ 2 }{ O }_{ 3 }^{ 2- }\longrightarrow { 2I }^{ - }+A,\) the product A is
- (a)
SO32-
- (b)
S2O42-
- (c)
S4O62-
- (d)
SO42-
The oxidation state of phosphorus is + 3 in
- (a)
phosphorus acid
- (b)
phosphoric acid
- (c)
metaphosphoric acid
- (d)
pyrophosphoric acid
The oxidation number of iodine ranges from
- (a)
- 1 to + 7
- (b)
- 1 to - 7
- (c)
+ 1 to + 7
- (d)
-1 to + 1
In alkaline medium manganese in MnO4- ion is reduced to MnO2 . The change in its oxidation number is
- (a)
2
- (b)
3
- (c)
5
- (d)
7
In which one of the following reactions H2O2 acts as an oxidising agent?
- (a)
\({ 2I }^{ - }+2{ H }^{ + }+{ H }_{ 2 }{ O }_{ 2 }\longrightarrow { I }_{ 2 }+2{ H }_{ 2 }{ O }\)
- (b)
\({ Ag }_{ 2 }O+{ H }_{ 2 }{ O }_{ 2 }{ \longrightarrow 2Ag+{ H }_{ 2 }{ O } }+{ O }_{ 2 }\)
- (c)
\(2Mn{ O }_{ 4 }^{ - }+6{ H }^{ + }+5{ H }_{ 2 }{ { O }_{ 2 } }{ \longrightarrow 2M{ n }^{ 2+ }+{ 8H }_{ 2 }{ O } }+{ 5O }_{ 2 }\)
- (d)
\({ O }_{ 2 }+2{ H }_{ 2 }{ O }_{ 2 }{ \longrightarrow { 2O }_{ 2 }+{ 2H }_{ 2 }{ O } }\)
CO2 is
- (a)
an oxidising agent
- (b)
a reducing agent
- (c)
a dehydrating agent
- (d)
a bleaching agent
Which one of the following will oxidise Mn2+ to MnO4-?
- (a)
CO2
- (b)
SO2
- (c)
SnO2
- (d)
PbO2
The oxidation number of sulphur in Na2S4O6 is
- (a)
2.5
- (b)
2 and 3 (two S have + 2 and the other two have + 3)
- (c)
2 and 4 (two S have + 2 and the other two have + 4)
- (d)
5 and 0 (two S have + 2 and the other two have 0)
The reaction, \({ 3ClO }^{ - }(aq)\longrightarrow { ClO }_{ 3 }^{ - }(aq)+2{ Cl }^{ - }(aq),\) is an example of
- (a)
oxidation
- (b)
reduction
- (c)
disproportionation
- (d)
decomposition
The oxidation number of carbon in C12H22O11 is
- (a)
12
- (b)
22
- (c)
11
- (d)
Zero
For the following reaction in the acidic solution \(Mn{ O }_{ 4 }^{ - }+8{ H }^{ + }+5e\longrightarrow Mn^{ 2+ }+4{ H }_{ 2 }O\) which of the following gives the oxidation numbers of the manganese on each side of the equation.
- (a)
+ 4 to + 2
- (b)
-1 to + 2
- (c)
+ 7 to + 5
- (d)
+ 7 to + 2
The oxidation state of chemical carbon is
- (a)
0
- (b)
1
- (c)
2
- (d)
3
The oxidation number of S in S2O32- is
- (a)
0
- (b)
- 2
- (c)
+ 2
- (d)
+ 6
The brown ring complex compound is formulated as \([Fe\left( { H }_{ 2 }O \right) _{ 5 }(NO)]{ SO }_{ 4 }.\) The oxidation state of iron in this compound is
- (a)
0
- (b)
1
- (c)
2
- (d)
3
In which reaction there is change in oxidation number of Nitrogen atom?
- (a)
\({ N }_{ 2 }{ O }_{ 5 }+{ H }_{ 2 }O\longrightarrow 2HN{ O }_{ 3 }\)
- (b)
\({ NH }_{ 4 }OH\longrightarrow { NH }_{ 4 }^{ + }+OH\)
- (c)
\(2N{ O }_{ 2 }+{ H }_{ 2 }O\longrightarrow HN{ O }_{ 3 }+HN{ O }_{ 2 }\)
- (d)
\(2N{ O }_{ 2 }\longrightarrow { N }_{ 2 }{ O }_{ 4 }\)
In which of the following compounds iron has the lowest oxidation state?
- (a)
FeSO4 (NH4)2SO4.6H2O
- (b)
K4Fe(CN)6
- (c)
K3 Fe (CN)6
- (d)
Fe(CO)5
Select the compound in which chlorine is assigned the oxidation number + 7.
- (a)
HClO4
- (b)
HClO2
- (c)
HClO3
- (d)
HCl
Oxidation numbr of Fe in \({ K }_{ 3 }Fe({ CN })_{ 6 }\) is
- (a)
+ 1
- (b)
+ 2
- (c)
+ 3
- (d)
+ 4
Oxidation number of P in \({ K }H_{ 2 }{ PO }_{ 2 }\) in
- (a)
+ 1
- (b)
+ 2
- (c)
+ 3
- (d)
+ 5
Oxidation number of iron in Potassium ferrocyanide \({ K }_{ 4 }[Fe(CN)_{ 6 }]\)in
- (a)
+ 2
- (b)
+ 3
- (c)
+ 4
- (d)
6
Oxidation numbr of oxygen atom in potassium peroxide is
- (a)
0
- (b)
\(????-\frac { 1 }{ 2 } \)
- (c)
- 4
- (d)
- 2
The colour of K2Cr2O7 changes from red orange to lemon orange yellow on treatment with aqueous KOH because of
- (a)
reduction of Cr (VI) to Cr (III)
- (b)
formation of chromium hydroxide
- (c)
conversion of dichromate ion to chromate
- (d)
oxidation of potassium hydroxide to potassium peroxide
A 2.5 mol of hydrazine N2H4 loses 25 mole of electrons being converted to a new compound X. Assume that all of the nitrogen appeas in the new compound, what is the oxidation state of nitrogen in compound X?
- (a)
- 1
- (b)
- 2
- (c)
+ 3
- (d)
+ 4