What do members of the same period in the periodic table all have in common?

Answer 1

The valence orbital (the outer shell) of the atom has the same number of electrons and hence elements in a given group have similar properties.
Elements in the same column have the same number of valence electrons and hence similar properties.

Answer 2

Each column in the Periodic Table represents one group. Each group's constituent elements have some similar properties which might be physical or chemical.

But the most common criteria to classify element in a particular group is the same no. of

electrons in the outermost shell.

Answer 3

If you get into chemistry its has to do with the number of electrons in the outer shell, but long before that was discovered elements were grouped into these columns because they share similar traits. One readily visible example of this is Sodium (Na) and in one row below, Potassium (K). Both combine with Chlorine to make salts which taste very similar to each other. Both of which also react very violently to water. They are not identical, but chemically similar.

Answer 4

Elements in a group or column share the same valence electron configuration. This means they all have similar reactivity. See the Related Questions to the left for more information.

Answer 5

They have similar properties so are grouped together.

Answer 6

Elements in a group have the same number of valence electrons and hence they have similar chemical and physical properties.

Answer 7

They have the same energy level (or shell).

Answer 8

valance electrons.

Answer 9

Atomic Weights

Answer 10

What he said