Electronic configuration of a transition element X in +3 oxidation state is [Ar] 3d⁵. What is its atomic number ?

1

(a)

25

(b)

26

(c)

27

(d)

24

The electronic configuration of Cu (II) is 3d⁹ whereas that of Cu (I) is 3d¹⁰ . Which of the following is correct ?

1

(a)

Cu (II) is more stable

(b)

Cu (II) is less stable 

(c)

Cu (I) and Cu (II) are equally stable

(d)

Stability of Cu (I) and Cu (II) depends on nature of copper salts

Metallic radii of some transition elements are given below. Which of these elements will have hig

Element	Fe	Co	Ni	Cu
Metallic	126	125	125	128

1

(a)

Fe

(b)

Ni

(c)

Co

(d)

Cu

Generally transition elements form coloured salts due to the presence of unpaired electrons. Which of the following compounds will be coloured in solid state ?

1

(a)

Ag₂SO₄

(b)

CuF₂

(c)

ZnF₂

(d)

Cu₂CI₂

On addition of small amount of KMnO₄ to concentrated H₂SO₄, a green oily compound is obtained which is highly explosive in nature, Identify the compound from the following.

1

(a)

Mn₂O₇

(b)

MnO₂

(c)

MnSO₄

(d)

Mn₂O₃