Ions Continued Unit 3 Topic 2

Charges Because elements in the same group (column) of the Periodic Table have the same number of valence electrons They also tend to form ions with the same charge

Oxidize (lose electrons) to form Positive Ions Charges Elements in columns 1-13 tend to undergo Oxidation (lose electrons) and form Positive ions. Oxidize (lose electrons) to form Positive Ions

Reduces (gains electrons) to form Negative Ions Charges Elements in columns 15-17 tend to undergo Reduction (gain electrons) and form Negative ions. Reduces (gains electrons) to form Negative Ions

Oxidation vs Reduction How am I going to remember these terms? O -Oxidation I -Is L -Loss R -Reduction G -Gain

Oxidation States The common oxidation state (ion charge) for elements can be predicted by their position on the Periodic Table

Common Oxidation States (Charges) +1 +2 +3 + or -4 -3 -2 -1 ~Charges Vary~ Color Page 2 of your PT Coloring book.

Octet Rule When elements react by losing or gaining electrons, they will lose or gain the number of electrons needed to become more stable The most stable electron configuration is a completely filled energy level Which means you have a filled valence shell of 8 valence electrons known as the octet rule (except Hydrogen and Helium)

8 is Great Which means you have a filled valence shell of 8 valence electrons known as the octet rule Or in the case of Hydrogen and Helium 2 electrons or zero electrons

Bonding Positive and negative ions are attracted to each other (because of their opposite charges) and combine to form ionic compounds. When ions combine to form compounds they must balance out their charges so that the compound ends up with no charge (electrically neutral)

The POSTIVE ion (cation) always goes FIRST! Predicting… We can predict the formulas for ionic compounds by determining the number of each ion (cation and anion) that is needed to cancel each other’s charges Note: The POSTIVE ion (cation) always goes FIRST!

Cl Na IONIC bond is formed Valence Electrons? Valence Electrons? 7 1 How many does it want to gain or lose? GAIN 1 What’s the charge? -1 Valence Electrons? 1 How many does it want to gain or lose? LOSE 1 What’s the charge? +1

Sodium Chloride Na+1 + Cl-1  NaCl (+1) + (-1) = 0

O Li IONIC bond is formed Valence Electrons? Valence Electrons? 6 1 NEEDS ONE MORE! Valence Electrons? 6 How many does it want to gain or lose? GAIN 2 What’s the charge? -2 Valence Electrons? 1 How many does it want to gain or lose? LOSE 1 What’s the charge? +1

Lithium oxide Li+1 + O-2  Li2O 2(+1) + 1(-2) = 0 CrissCross Method

Barium Iodide Ba+2 + I-1  BaI2 (+2) + 2(-1) = 0

Magnesium phosphide Mg+2 + P-3  Mg3P2 3(+2) + 2(-3) = 0

Magnesium phosphide Mg+2 + P-3  Mg3P2 3(+2) + 2(-3) = 0

Ionic Bonding Na Cl Cl Ca Cl Ionic bonding occurs when a metal transfers one or more electrons to a nonmetal in an effort to attain a stable octet of electrons. For example, the transfer of an electron from sodium to chlorine can be depicted by a LDD. Na Cl Cl Ca Cl

O Cl P Na Ca Li Al Na+1 O-2 Na2O Anion Cation Valence 1Valence Lose 1 And Charge 6 valence Gain 2 – 2 Na 1Valence Lose 1 +1 Na+1 O-2 Na2O Ca Li Al

O Cl P Na Ca Li Al Na2O Anion Cation Valence 1Valence Lose 1 +1 And Charge 6 valance Gain 2 – 2 Na 1Valence Lose 1 +1 Na2O Ca Li Al

Naming Ionic Compounds What is an Ionic Compound? Positive Metal + Negative Nonmetal To name compounds: Positive Metal name + Negative nonmetal name (drop ending and add “ide” NaCl = sodium chloride Ba3P2 = barium phosphide

O Cl P F Na Sodium oxide Ca Li Al Ba Barium phosphide