7.4

Elements in the same group are more similar in their properties than elements in the same period. This is because these elements have the same # of valence electrons and their oxidation states are similar.

Elements in the same group tend to have similar properties because they have similar electron configurations but they have the same # of valence electrons.

K, Li, and Na have similar properties because they all react with air fast, they react with water fast as well.

When an atom of sodium reacts with a non-metal it tends to:

• Lose electrons
• Become a positive ion
• The electrical charge of the ion becomes +1
• Have an electron configuration of the element Neon
• Be more stable because the valence electrons are closer to the nucleus