Periodic Table Basics

Front

Periods on the periodic table are __________.

Back

Horizontal Rows

Front

The first energy shell can hold ______ electrons.

Back

2

Front

The number at the bottom of each square on the periodic table is the ...

Back

atomic mass

Front

Groups on the periodic table are __________.

Back

Vertical Columns

Front

In the periodic table, similar elements are arranged in vertical columns called groups. Some of the major groups include Group 1: alkali metals; Group 2: alkaline earth metals; Group 17: halogens; and Group 18: noble gases. Elements within each group have similar properties and characteristic behaviors because of their similar numbers of valence electrons. In what direction are groups arranged in the periodic table?

Back

Up and down.

Front

What is the atomic number of an element?

Back

The number of protons in the nucleus of an atom.

Front

What do elements in the same group of the periodic table have in common?

Back

They have similar chemical properties and the same number of valence electrons.

Front

What is the significance of the atomic mass on the periodic table?

Back

It represents the average mass of an element's isotopes.

Front

What are alkali metals?

Back

They are elements in Group 1 of the periodic table, known for being highly reactive.

Front

What are noble gases?

Back

They are elements in Group 18 of the periodic table, known for being inert and non-reactive.