1. TRENDS
IN THE
PERIODIC TABLE

3. ATOMIC SIZE
- Estimated by measuring the distance between 2 neighboring atoms

4. FACTORS AFFECTING ATOMIC SIZE
PRINCIPAL QUANTUM NUMBER (n) OF THE VALENCE ELECTRON – the farther the valence electron is from the nucleus, the greater is the atomic size.
EFFECTIVE NUCLEAR CHARGE (Zeff ) – charge “felt” by the valence electron due to the attractive force of the protons (Z) and the shielding effect (S) by the core electrons
Zeff = Z - S

5. +1-0=+1
+2-0=+2
+4 -2=+2
+3 -2=+1

7. EFFECT OF CHARGE ON SIZE OF IONS

8. IONIZATION ENERGY (IE) - Amount of energy needed to remove an electron from an atom.

10. ELECTRON AFFINITY (EA) – amount of energy needed to add electrons to an atom

12. ELECTRONEGATIVITY – tendency of an atom to attract electrons; guided by the octet rule.