Reminders/Info Quiz tomorrow – Metals, nonmetals, metalloids, electron configuration, valence electrons, electron dot structures Homework due Friday at the beginning for raffle chance Friday you will be able to do makeup work in class – bring your textbook

Can you do this. Explain why atoms are neutral in charge Can you do this? Explain why atoms are neutral in charge. HINT: think about the charges and numbers of the subatomic particles 3

Atoms have equal numbers of protons and electrons Protons and electrons have opposite charges Equal and opposite charges cancel out

Ion Formation 12-15-10 Cornell Notes

What is an ion? A single atom or groups of atoms with either a positive or negative charge. Cation: positively charged ion Anion: negatively charged ion

How do Ions form? Ions form when atoms lose or gain valence electrons. Lose electrons = Make a CATION Gain electrons = Make an ANION Na Na+

- Na + Cl  Na+ + Cl Octet Rule Atoms lose, gain or share electrons in order to acquire the stable electron configuration of a noble gas. Lose all valence electrons, or gain electrons until it has 8 - Na + Cl  Na+ + Cl Cation, Like Ne Anion, Like Ar

Trends in Ion Formation Groups 1 to 4 give their valence electrons away 1 2 13 14 Li  Li+ Mg Mg2+  B  B3+

Trends in Ion Formation Groups 5 to 7 take electrons 3- P  P 5 6 7 2- O  O - F  F

Trends in Ion Formation Group 8 doesn’t form ions (noble gases) They already have the lucky 8 electrons! 8

Example 1 Ca2+ What would be the ion for Calcium (Ca)? Group 2 # valence electrons 2 Gain/Lose electrons Lose Charge 2+ Ion Ca2+

Example 2 B3+ What would be the ion for Boron (B)? Group 3 Gain/Lose electrons Lose Charge 3+ Ion B3+

Example 3 P3- What would be the ion for Phosphorus (P)? Group 5 Gain/Lose electrons Gain Charge 3- Ion P3-

Worksheet For each element, identify: You may work in groups The group Whether the element gains or loses electrons The charge of the ion The written form of the ion You may work in groups 2 bonus points if you get all the answers correct Hand in your work at the end of class