The elements are arranged in the increasing order of their atomic number and repeating periodic properties.
they are grouped by there collums
What are some ways the stars in the photo could be grouped or classified
Because all of the elements in the groups or families all have similar qualities. For example, all of the elements in the noble gas family are grouped together because they are stable elements.
there are grouped in clomesand rows ad groups
Johann grouped together Earth, Wind, and Fire as the first three elements.
Minarols
How are elements classified
Group are based on similar properties. The elements having same chemical properties are grouped together.
the Periodic Table of elements
they are grouped by the number of valence electrons.
hydrogen
Dmitri Mendeleev