C2.5 - EXPLAINING TRENDS

C2.5 - EXPLAINING TRENDS

1. THIS ELECTROSTATIC ATTRACTION DEPENDS ON:

   • DISTANCE BETWEEN OUTERMOST ELECTRONS AND THE NUCLEUS
   • THE NUMBER OF OCCUPIED INNER SHELLS OF ELECTRONS WHICH PROVIDE A SHIELDING EFFECT
   • SIZE OF POSITIVE CHARGE ON NUCLEUS/NUCLEAR CHARGE

2. TRENDS IN REACTIVITY (AS YOU GO DOWN GROUP) CAN BE EXPLAINED BY ATTRACTION BETWEEN ELECTRONS IN OUTERMOST SHELL + THE NUCLEUS

3. IN DECIDING HOW EASY IT IS FOR ATOMS TO LOSE/GAIN ELECTRONS FROM OUTER SHELL WE MUST TAKE INTO ACCOUNT THE 3 FACTORS OF ELECTROSTATIC ATTRACTION.

   • ELECTRONS ARE EASIER FOR THE LARGER ATOMS TO LOSE AS YOU GO DOWN THE GROUP
   • ELECTRONS ARE HARDER FOR THE LARGER ATOMS TO GAIN AS YOU GO DOWN THE GROUP