1 d) The Periodic Table

Vertical column in the Periodic Table. All elements in the same group have the same number of outer shell electrons and similar chemical properties.

Unreactive

Horizontal row in the Periodic Table. All elements in the same period have the same number of occupied shells.

How electrons are arranged in the shells in an atom.

Same number of electrons

Group 0 or 8 on the Periodic Table

Atoms generally lose, gain or share electrons in order to have eight electrons in their outer shell (except the first shell which is full with 2).

Table in which elements are arranged in order of increasing atomic number (and in terms of chemical and physical properties).

Where electrons are found outside the nucleus (also called energy shells).

Electrostatic force of attraction on an electron from the nucleus is offset by inner shell electrons (inner electrons shield/screen the outer ones).