51)

In a multi-electron atom, which of the following orbitals described by the three quantum numbers will have the same energy in the absence of magnetic and electric fields ?
I . n = 1, l = 0, m = 0
II. n = 2, l = 0, m = 0
III. n = 2, l = 1, m = 1
IV n = 3, l = 2, m = 1
V. n = 3, l = 2, m = 0

JEE Physics

A)

IV & V

B)

III & IV

C)

II & III

D)

I & II

52)

Which one of the following oxidation states is not possible in metal carbonyls ?

 

JEE Physics

A)

+1

B)

-1

C)

0

D)

2

E)

-3

53)

The oxidation number of chromium in potassium dichromate is

JEE Physics

A)

+2

B)

+4

C)

+1

D)

+8

E)

+6

54)

The loss of electron is termed as

JEE Physics

A)

oxidation

B)

reduction

C)

combustion

 

D)

neutralization

55)

State the oxidation number of carbonyl carbon in methanal and methanoic acid, respectively

1) 0 and 0

2) 0 and + 2

3) + 1 and + 2

4) + 1 and + 3

JEE Physics

A)

0 & 0

B)

0 & +2

C)

+1 & +2

D)

+1  & +3

56)

Which quantities are conserved in all redox reactions?

 

JEE Physics

A)

Charge only

 

B)

Both charge and mass

C)

Mass only

D)

Neither charge nor mass

57)

Oxidation number of sulphur in Caro's acid is

JEE Physics

A)

6

B)

8

C)

4

D)

7

58)

Oxidation states of the metal in the minerals haematite and magnetite, respectively, are

JEE Physics

A)

II, III in haematite and III in magnetite,

 

B)

II in haematite and II, III in magnetite

C)

III in haematite and II, III in magnetite

D)

II, III in haematite and II in magnetite

59)

The oxidation number of C in HCN and HNC respectively are:

JEE Physics

A)

+ 2, + 2

B)

+ 4, +4

 

C)

+ 2, + 4

D)

-2, -2

60)

Phosphorus has the oxidation state of +3 in

JEE Physics

A)

Hypophosphorous acid

B)

Orthophosphoric acid

C)

Metaphosphoric acid

D)

Phosphorous acid