Attempts of elements classification: The fundamentals of the periodic table

The video explains that atoms are the fundamental units of matter, and elements are substances made of one type of atom. The periodic table organizes elements by atomic numbers and properties into periods (horizontal rows) and groups (vertical columns). Each period and group has specific characteristics, such as the number of electron orbitals or outer shell electrons. The atomic number increases across periods and down groups, providing a systematic way to study elements.

What is the primary reason for arranging elements in a periodic table?

• To categorize elements by their color

• To group elements by their size

• To organize elements by their atomic numbers and properties

• To list elements alphabetically

How many elements are there in the first period of the periodic table?

• Eighteen

• Two

• Three

• Seven

What is a common characteristic of elements within the same period?

• They have identical chemical properties

• They have similar atomic masses

• They have the same number of protons

• They have the same number of orbitals

Which group in the periodic table contains elements with one electron in their outermost orbital?

• Group 1

• Group 2

• Group 8

• Group 18

What does the atomic number of an element represent?

• The number of neutrons in the atom

• The number of electrons in the outer shell

• The number of protons in the atom

• The total number of orbitals