Element ₅₈Ce belongs to:

1. s-block elements

2. p-block elements

3. d-block elements

4. f-block elements

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

An element having the electronic configuration of its atom ns² np² should have similar properties to those of:

1. Sodium

2. Carbon

3. Magnesium

4. Oxygen