On the periodic table, lithium and beryllium are in different groups. Which statement describes why the two elements are in different groups?(1 point)

Responses

They have a different number of electrons in their outer shells.
They have a different number of electrons in their outer shells.

They have different atomic numbers.
They have different atomic numbers.

They are different colors.
They are different colors.

They have a different number of electron shells.

1 answer

The correct statement that describes why lithium and beryllium are in different groups is:

They have a different number of electrons in their outer shells.

Lithium (Li) has one electron in its outer shell, while beryllium (Be) has two electrons in its outer shell. This difference in the number of valence electrons is what places them in different groups on the periodic table.