Electron Configuration and Valence Electrons

The video tutorial explains how to determine the number of valence and core electrons in atoms using examples like oxygen, selenium, cesium, iron, and europium. It highlights the importance of electron configuration and periodic table columns in identifying valence electrons. The tutorial also distinguishes between s, p, d, and f block elements and their respective valence electron configurations.

What is the total number of electrons in an oxygen atom?

• 8

• 12

• 6

• 10

How many valence electrons does selenium have?

• 4

• 5

• 6

• 7

What is the total number of core electrons in selenium?

• 28

• 30

• 32

• 34

How many valence electrons does cesium have?

• 3

• 4

• 2

• 1

What is the total number of core electrons in cesium?

• 55

• 54

• 53

• 52

In which block is iron located in the periodic table?

• f-block

• d-block

• p-block

• s-block

How many valence electrons does iron have?

• 9

• 8

• 7

• 6

What is the noble gas configuration for iron?

• [Ne] 3s2 3p6

• [Ar] 4s2 3d6

• [Xe] 6s2 5d6

• [Kr] 5s2 4d6

How many valence electrons does europium have?

• 7

• 9

• 8

• 10

Which noble gas is used in the configuration of europium?

• Krypton

• Argon

• Neon

• Xenon