Modern Periodic Table

What's the modern periodic table pretty much like?

The one produced by Henry Moseley around 1914.

How did Moseley arrange the elements?

According to increasing atomic number rather than by mass.

What did Moseley's arrangement fix?

A few elements that Mendeleev had put out of place using atomic mass

What did Moseley add?

Noble gases which had been discovered in 1890s

What did Glen Seaborg suggest?

The f-block elements fit into the periodic table, though they're usually shown separated from the main part of the table.

How is the periodic table arranged?

Periods, or rows, and groups, or columns.

What do all elements within a period have?

The same number of electron shells

What do elements within a period laving the same number of electron shells result in?

Repeating patterns of physical and chemical properties across a period, known as periodicity.

What do all elements within a group have?

The same number of electrons in their outer shell.

What does having same number of electrons in outer shell within a group mean?

They have similar physical and chemical properties

What does the group number tell you?

The number of electrons in the outer shell.

What are the only elements where the group number doesn't tell you how many eectrons are in their outer shell?

Group 0 elements, they have full outer shells