PHYSICAL CHEMISTRY
b y : SHAILENDRA KR.
Meq. Approach
Classes at: -
SCIENCE TUTORIALS; Opp. Khuda Baksh Library, Ashok Rajpath, Patna
PIN POINT STUDY CIRCLE; House No. 5A/65, Opp. Mahual Kothi, Alpana Market, Patna
Topic: Oxidation & Reduction
01. Oxidation state of oxygen in H2O2 is:
(a) –2
(b) –1
(c) +1
(d) +2
02. The oxidation number of phosphorus in Mg2P2O7 is:
(a) +5
(b) -5
(c) +6
(d) -7
03. In CH2Cl2, the oxidation number of C is:
(a) -4
(b) +2
(c) Zero
(d) +4
04. Which compound has oxidation number of carbon
equal to zero?
(a) C6H6
(b) CH3
(c) C2H4
(d) C6H12O6
05. Oxidation state of +1 for phosphorus is found in:
(a) H3PO3
(b) H3PO4
(c) H3PO2
(d) H4P2O7
06. The oxidation number of sulphur in H2S2O8 is:
(a) +2
(b) +6
(c) +7
(d) +14
07. Oxidation number of sulphur in Na2SO4 is:
(a) +2
(b) +4
(c) +6
(d) -2
08. A compound contains atoms X, Y, Z. The oxidation
number of X is +2, Y is +5 and Z is -2. The possible
formula of the compound is:
(a) XY1Z2
(b) Y2(XZ3)2
(c) X3(YZ4)2
(d) X3(Y4Z)2
09. Oxidation number of carbon in KCN is:
(a) +2
(b) -2
(c) +1
(d) +3
10. The Oxidation number of Cr in [Cr(NH3)4Cl2]+ is:
(a) +3
(b) +2
(c) +1
(d) Zero
11. Oxidation number of nitrogen in AgNO3 is:
(a) +5
(b) -3
(c) +3
(d) -2
12. In which compound, oxygen has an oxidation state
of +2 ?
(a) H2O2
(b) H2O
(c) OF2
(d) CO
13. The oxidation state of hydrogen in CaH2 is:
(a) +1
(b) -1
(c) Zero
(d) +2
14. Sulphur has the highest oxidation state in:
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
(b) SO3
(a) SO2
(b) H2SO3
(d) H2S
In the conversion of Br2 to BrO3–, the oxidation state
of bromine changes from:
(a) 0 to +5
(b) -1 to +5
(c) 0 to -3
(d) +2 to +5
In the reduction of dichromate by Fe(II), the number
of electrons involved per chromium atom is:
(a) 3
(b) 1
(c) 2
(d) 4
For reducing one mole of Fe2+ ion to Fe, the number
of faraday of electricity is:
(a) 2
(b) 1
(c) 1.5
(d) 4
The number of mole of oxalate ions oxidised by one
mole of MnO4– is:
(a) 1/5
(b) 2/5
(c) 5/2
(d) 5
Maximum oxidation state is present in:
(a) CrO2Cl2 and MnO4–
(b) MnO2
(c) [Fe(CN)6]3– and [Co(CN)6]3–
(d) MnO
When Sn (IV) chloride is treated with excess HCl,
the complex [SnCl6]2– is formed. The oxidation state
of Sn in this complex is:
(a) +6
(b) -2
(c) +4
(d) -5
Oxidation state of oxygen atom in potassium
superoxide (KO2) is:
(a) -1/2
(b) Zero
(c) +1/2
(d) -2
When KMnO4 is reduced with oxalic acid in acid
medium, the oxidation number of Mn changes from:
(a) +7 to +4
(b) +6 to +4
(c) +7 to +2
(c) +4 to +2
Oxidation number of chromium in K2Cr2O7 is:
(a) +2
(b) +3
(c) +6
(d) -4
Chlorine has +1 oxidation state in:
(a) HCl
(b) HClO3
(c) Cl2O
(d) ICl3
Iodine has +7 oxidation state in:
(b) H3IO5
(a) HIO4
(c) H5IO6
(d) All of these
26. Which reaction indicates the oxidising behaviour of
H2SO4 ?
(a) 2PCl5 + H2SO4 ––––→ 2POCl3 + 2HCl + SO2Cl2
(b) 2NaOH + H2SO4 ––––→ Na2SO4 + 2H2O
(c) NaCl + H2SO4 ––––→ NaHSO4 + HCl
(d) 2HI + H2SO4 ––––→ I2 + SO2 + 2H2O
27. If three electrons are lost by a metal ion M3+, its final
oxidation number will be:
(a) Zero
(b) +6
(c) +2
(d) +4
28. Oxidation number of N in N3H is:
(a) -3
(b) +3
(c) Zero
(d) -1/3
29. The oxidation number of N in NH3 is:
(a) -3
(b) +3
(c) Zero
(d) 5
30. Oxidation number of S in S2Cl2 is:
(a) +1
(b) +6
(c) Zero
(d) -1
31. The oxidation number of Fe in K4Fe(CN)6 is:
(a) +2
(b) +3
(c) +4
(d) +6
32. HCO3– contains carbon in the oxidation state:
(a) +5
(b) +1
(c) +4
(d) Zero
33. In nitric oxide (NO) the oxidation state of N is:
(a) -2
(b) +1
(c) -1
(d) +2
34. In which of the following N has lowest oxidation
number ?
(a) NO
(b) NO2
(c) N2O
(d) N2O5
35. Oxidation number of S in S2O32– is:
(a) +2
(b) -2
(c) 4
(d) Zero
36. Oxidation number of Fe in K3[Fe(CN)6] is:
(a) +2
(b) +3
(c) +4
(d) +1
37. The maximum oxidation number of transition metals
may be:
(a) +4
(b) +6
(c) +8
(d) +10
38. Carbon is in the lowest oxidation state in :
(a) CH4
(b) CCl4
(b) CO2
(d) CF4
39. Oxidation state of oxygen is -1 in the compound :
(a) NO2
(b) MnO2
(c) PbO2
(d) Na2O2
40. In sodium hydride, oxidation state of sodium is:
(a) Zero
(b) +1
(c) -1
(d) +2
41. In MgH2, Oxidation number of hydrogen is:
(a) -1
(b) +1
(c) -2
(d) +2
42. The oxidation number of iodine in IF5 is:
(a) +5
(b) -5
(c) -1
(d) +1
43. What is the ox. no. of Mn in K2MnO4?
(a) +4
(b) +6
(c) +2
(d) +8
44. With which element oxygen shows positive oxidation
state in its compounds?
(a) Na
(b) Cl
(c) N
(d) F
45. The oxidation number of Mn in MnO2 is:
(a) +4
(b) +6
(c) +2
(d) -4
46. The oxidation number of P in KH2PO2 is:
(a) +1
(b) +3
(c) -3
(d) +5
47. The oxidation number of Cl in KClO3 is:
(a) +5
(b) -5
(c) +3
(d) -3
48. One mole of N2H4 loses 10 mole of electrons to form
a new compound Y, Assuming that all nitrogen
appears in the new compound, what is the oxidation
number of nitrogen in Y (There is no change in the
oxidation state of hydrogen)?
(a) -3
(b) +3
(c) +5
(d) +1
49. The reaction is balanced if,
5H2O2 + XClO2 + 2OH– ––––→ XCl– + YO2 + 6H2O
(a) X = 5, Y = 2
(b) X = 2, Y = 5
(c) X = 4, Y = 10
(d) X = 5, Y = 5
50. The oxidation state of nitrogen in NH4NO3 is:
(a) -3 and +5
(b) +3 and +5
(c) +5
(d) +3
51. The oxidation number of nitrogen in NH2OH is:
(a) +1
(b) -1
(c) -3
(d) -2
52. Oxidation number of As atom in H3AsO4 is:
(a) +5
(b) +6
(c) +4
(d) -3
53. Oxidation number of chlorine in HOCl is:
(a) Zero
(b) -1
(c) +1
(d) +2
54. Nitrogen has fractional oxidation number in:
(a) N2H4
(b) NH4
(c) HN3
(d) N2F2
55. Oxidation of thiosulphate(S2O32–) ions by iodine gives
(a) SO3–
(b) SO42–
2–
(c) S4O6
(d) S2O82–
56. The charge on cobalt in [Co(CN)6]3– is:
(a) -6
(b) +3
(c) -3
(d) +6
57. The maximum oxidation state of osmium is :
(a) +7
(b) +8
(c) +10
(d) +6
58. In the compound KMnO4 and K2Cr2O7, the highest
oxidation state is of the element:
(a) K
(b) Mn
(c) Cr
(d) O
59. The maximum oxidation state of chromium is:
(a) +6
(b) +4
(c) +8
(d) +7
by: SHAILENDRA KR.
PHYSICAL CHEMISTRY
A
N
S
W
E
R
S
1.
b
31.
a
2.
a
32.
c
3.
c
33.
d
4.
d
34.
c
5.
c
35.
a
6.
b
36.
b
7.
c
37.
c
8.
c
38.
a
9.
a
39.
d
10.
a
40.
b
11.
a
41.
a
12.
c
42.
a
13.
b
43.
b
14.
b
44.
d
15.
a
45.
a
16.
a
46.
a
17.
a
47.
a
18.
c
48.
b
19.
a
49.
b
20.
c
50.
a
21.
a
51.
b
22.
c
52.
a
23.
c
53.
c
24.
c
54.
c
25.
d
55.
c
26.
d
56.
b
27.
b
57.
b
28.
d
58.
b
29.
a
59.
a
30.
a
1.
2.
Opp. Khuda Baksh Library, Ashok Rajpath, Patna - 4
House no. 5A/65, Opp. Mahual Kothi, Alpana Market, Patna
Page No.: 3