Photo by Ra’ike Ionic Compounds

+ Chemical reactions occur when atoms gain, lose, or share electrons. Metals Nonmetals Metals _____________ electrons. This gives them a ____ charge. Positive ions are called ________. When elements lose electrons and increase their charge, we say that they have been _________. lose or donate + cations oxidized

_ Chemical reactions occur when atoms gain, lose, or share electrons. Metals Nonmetals Nonmetals ___________ electrons. This gives them a ____ charge. Negative ions are called _______. When elements gain electrons and lower their charge, we say that they have been ________. gain/accept _ anions reduced

Remember that the charge of an ion can be determined by its place on the Periodic Table. +1 +2 +3 -3 -2 -1 ±4

Determine the charge of each of the elements on your notes. +2 -1 -2 -2 +1 -1 +1 +1 -1 -3 +2 -3 +2

Metals lose/donate electrons and nonmetals gain/accept electrons Because of this metals react with nonmetals to create IONIC COMPOUNDS! NaCl Fe3O2 MgBr2 K2S ZnF2

The Noble Gases What is special about group 18? They are inert gases because they have a full octet (8) of valence electrons. This makes them the least reactive elements on the periodic table.

Important Vocabulary: When atoms gain or lose electrons, they become ions. Ions have either a positive or negative charge! + 1 Sodium ion Sodium atom

Ionic compounds are formed when metals donate electrons and get a positive charge and nonmetals gain electrons and get a negative charge.

Sodium Chloride Formula Unit The smallest particle of an ionic compound is a FORMULA UNIT. This is a theoretical unit that represents the ratio of ions in the crystal. Sodium Chloride (NaCl) Sodium Chloride Formula Unit

RbCl HBr KCl LiF RbBr HCl LiF NaBr KF CsI KBr NaI LiCl FrCl HF + 1 Group 1 elements have a ___ charge. Group 17 elements have a ___ charge. This causes them to combine in 1:1 ratio + 1 - 1 RbCl HBr KCl LiF RbBr HCl LiF NaBr KF CsI KBr NaI LiCl FrCl HF

MgSe CaO BeS BaTe SrSe BeO MgS SrO BaSe CaTe CaS BeSe MgO SrS BaO + 2 Group 2 elements have a ___ charge. Group 16 elements have a ___ charge. This causes them to combine in 1:1 ratio + 2 - 2 MgSe CaO BeS BaTe SrSe BeO MgS SrO BaSe CaTe CaS BeSe MgO SrS BaO

Creating a Lewis Dot Structure for an Ionic Compound Ionic compounds have much simpler Lewis structures than covalent compounds. NaCl Na + Cl - Sodium donates 1 electron and chlorine gains one electron. This gives makes them ions.

The metal cation is NOT required to have parentheses around it. Na Cl + - Notice that the metal cation has no electrons around it. This represents that it donated its valence electrons. The nonmetal anion has 8 valence electrons because it gained enough to have a full valence shell. Important Note: The metal cation is NOT required to have parentheses around it. Na Cl + -

Creating a Lewis Dot Structure for an Ionic Compound MgCl2 Cl - Mg +2 Cl - Remember, parentheses around the metal are optional. If you are confused about which charge to place next the ion, then just use your Periodic Table to see what the charge should be!

K O K K2O Creating a Lewis Dot Structure for an Ionic Compound + -2 + Create the Lewis dot diagram for the ionic compound shown below on your notes. K2O K + O -2 K + Remember, parentheses around the metal are optional.

Remember, parentheses around the metal are optional. Write Lewis Dot Structures for the ionic compounds found on your notes. Remember, parentheses around the metal are optional.

Creating a Lewis Dot Structure for an Ionic Compound It is also important that you can identify the correct structures of polyatomic ions. Polyatomic ions are covalently bonded elements that have a charge!

Creating a Lewis Dot Structure for an Ionic Compound To determine how many electrons should be present in the diagram of a polyatomic ion, you should use the formula below. Number of Electrons = Total Valence - Charge SO4-2 = 6 + 4(6) - (-2 ) = 32 e- Be Careful!

Which structure below represents the sulfate ion (SO4-2) correctly? = 6 + 4(6) - (-2 ) = 32 e- Which structure below represents the sulfate ion (SO4-2) correctly? A C B D

Determine how many electrons should be each of the polyatomic ions on your notes.