Understanding the Periodic Table

The video tutorial explains the periodic table's structure, focusing on atomic and mass numbers. It describes how elements are arranged by increasing atomic number, which is the count of protons in an atom's nucleus. The tutorial uses hydrogen, helium, and lithium to illustrate these concepts. It also introduces the mass number, which is the sum of protons and neutrons, and explains how it varies among elements.

How are elements arranged in the periodic table?

• Alphabetically

• By decreasing atomic number

• Randomly

• By increasing atomic number

What is the atomic number of hydrogen?

• 0

• 1

• 2

• 3

How many protons does a helium atom have?

• 4

• 3

• 2

• 1

What is the atomic number of lithium?

• 2

• 3

• 5

• 4

As you move across a row in the periodic table from left to right, the atomic number:

• Decreases by one

• Increases by one

• Increases by two

• Remains the same

What does the mass number represent?

• Number of neutrons

• Number of protons plus neutrons

• Number of protons

• Number of electrons

What is the mass number of hydrogen?

• 0

• 1

• 3

• 2

How many neutrons does helium have?

• 1

• 4

• 3

• 2

What is the mass number of lithium?

• 6

• 7

• 8

• 9

What makes the atomic number unique for each element?

• Number of electrons

• Number of protons

• Number of neutrons

• Number of atoms