Element ₅₈Ce belongs to:

1. s-block elements

2. p-block elements

3. d-block elements

4. f-block elements

The screening effect of 'd' electrons is:

1. Much less than s-electrons.

2. Much more than s-electrons.

3. Equal to s-electrons.

4. Equal to p-electrons.

Correct statement regarding transuranic elements is :

1. They have higher atomic number than uranium.

2. They are lighter than uranium.

3. They have lower atomic number than uranium.

4. They have same atomic number as uranium.

General electronic configuration of outermost and penultimate shell of an atom is
(n - 1)s² (n - 1) p⁶ (n - 1)d^x ns². If n = 4 and x = 5, the number of proton in the nucleus is:

1. > 25

2. < 24

3. 25

4. 30

The maximum number of valence electrons possible for atoms in the second period of the periodic table is:

1. 18

2. 10

3. 8

4. 2

The element having atomic number 19, is:

1. an inert gas

2. a metal with oxidation number +1

3. a non-metal with oxidation number -3

4. a metal with oxidation number -3

Which of the following has the least density?

1. Na

2. Li

3. Mg

4. K

The order of basic character of given oxides is:

1. Na₂O > MgO > Al₂O₃ > CuO

2. MgO > Al₂O₃ > CuO > Na₂O

3. Al₂O₃ > MgO > CuO > Na₂O

4. CuO > Na₂O > MgO > Al₂O₃

An element R forms the highest oxide R₂O₅. R belongs to:

1. 13th  group

2. 15th group

3. 16 th group

4. 2nd group

Transition elements exhibit variable oxidation states because they release electrons from the following orbits:

1. ns and np orbits

2. (n-1)d and ns orbits

3. (n-1)d orbits

4. ns orbits