Periodic trends re-teach Ionic Radii
Why? Majority answered incorrectly. Reteach necessary Quiz will be given after presentation Points added back on to test grade Test grades will be entered later today
What is a radius?
What is an ion? An ion is a charged atom. Remember: Electrons have a negative charge!!!! A cation is a positive ion that has lost electron(s) An anion is a negative ion that has gained electron(s)
Important Trends Ionic Radii- distance from the nucleus to the outermost electron in an ion
Ionic Radius: WHAT IS THE TREND? Increases moving down a family Due to an increase in energy levels
Ionic Radius: WHAT IS THE TREND? Varies as you go across a period from right to left This is because as you go across a period, atoms switch from cations to anions.
Ionic Radius Varies Increases
Ionic radius: Why does this trend occur? Increases Going Down a Group Due to: an increase in energy levels Varies Going Across a Period Due to: switching from cations to anions
When comparing two ions: Ask yourself, “What Noble Gas does it become? The noble gas further down the periodic table has the larger ionic radius The noble gas further up the periodic table has the smaller ionic radius.
Practice Which element has the larger ionic radius? Step 1: Write the noble gas they become Cl1- ____ or Br1- ____ Step 2: Which noble gas is lower on the periodic table? Step 3: Select the ion that goes with the noble gas chosen in step 2.
Practice: Larger ionic radius O2- ____ or Ca2+____ B3+ ____ or S2- _____
Practice Which element has the smaller ionic radius? Step 1: Write the noble gas they become F1- ____ or Li1+____ Step 2: Which noble gas is higher on the periodic table? Step 3: Select the ion that goes with the noble gas chosen in step 2.
Practice: smaller ionic radius S2- ____ or Al3+____ Fr1- ____ or Te2-_____
Quiz time! Clear desk for quiz You only need a writing utensil Periodic table will be provided