Naming Chemical Compounds

Ionic Compounds An ionic compound is a compound that is formed when a positive ion and a negative ion coming together and stick together because of their opposite charges. An ionic compound is a compound that is formed when a positive ion and a negative ion coming together and stick together because of their opposite charges. Remember – ions are atoms that carry a charge because they have lost or gained electrons. Remember – ions are atoms that carry a charge because they have lost or gained electrons. Metals will lose their electrons (wimps) and form positive ions. Metals will lose their electrons (wimps) and form positive ions. Nonmetals will gain electrons (bullies) and form negative ions. Nonmetals will gain electrons (bullies) and form negative ions. All stable ions are “noble” – they will have a full outer electron shell. All stable ions are “noble” – they will have a full outer electron shell.

Naming Ionic Compounds All compounds have a first and last name just like you – ionic compounds are no different… All compounds have a first and last name just like you – ionic compounds are no different… The first name is the name of the positive ion – usually the metal. The first name is the name of the positive ion – usually the metal. The second name is the name of the negative ion – usually the nonmetal – only it has been shortened and given an “IDE” ending. The second name is the name of the negative ion – usually the nonmetal – only it has been shortened and given an “IDE” ending. Overall – it kinds looks like this… Overall – it kinds looks like this… Metal nonmetide Example: CaCl 2 & K 2 O Example: CaCl 2 & K 2 O Calcium chloride & Potassium oxide

Compounds With Shifty Metals There are several metals on the periodic table that are “shifty”. They are capable of having more than one ionic charge. Of course, being metals, this charge is positive. There are several metals on the periodic table that are “shifty”. They are capable of having more than one ionic charge. Of course, being metals, this charge is positive. These metals are: These metals are: –Copper – Cu – I & II –Iron – Fe – II & III –Lead – Pb – II & IV –Tin – Sn – II & IV When naming a compound, these metals must be identified not only with their name but with their charge. When naming a compound, these metals must be identified not only with their name but with their charge. The formulas of compounds that include these “shifty” metals do not have any Roman numerals in them. The formulas of compounds that include these “shifty” metals do not have any Roman numerals in them.

Naming Ionic Compounds With “Shifty” Metals These too, have a first and last name. These too, have a first and last name. The first name is the name of the metal. This name is followed by a Roman numeral in brackets – just to show what form of the “shifty” metal it is. The first name is the name of the metal. This name is followed by a Roman numeral in brackets – just to show what form of the “shifty” metal it is. The second name is the name of the nonmetal – shortened with the “IDE” ending. The second name is the name of the nonmetal – shortened with the “IDE” ending. Example: Cu 3 N & SnO 2 Example: Cu 3 N & SnO 2 Copper (I) nitride & Tin (IV) oxide

Polyatomic Ions A polyatomic ion is a cluster of atoms that travel together as a single unit that carries an overall charge. A polyatomic ion is a cluster of atoms that travel together as a single unit that carries an overall charge. Many of the polyatomic ions are negatively charged so when they are in an ionic compound they replace the nonmetal. Many of the polyatomic ions are negatively charged so when they are in an ionic compound they replace the nonmetal. The polyatomic ions you need to know are: The polyatomic ions you need to know are: Name (formula) charge Name (formula) charge –Hydroxide (OH) 1- –Nitrate (NO 3 ) 1- –Chlorate (ClO 3 ) 1- –Bicarbonate (HCO 3 ) 1- –Carbonate (CO 3 ) 2- –Sulfate (SO 4 ) 2- –Phosphate (PO 4 ) 3- –Ammonium (NH 4 ) 1+

Naming Polyatomic Compounds Polyatomic compounds also get two names just like we do. Polyatomic compounds also get two names just like we do. The first name will be the name of the positive ion – usually a metal – no changes are made to this first name. The first name will be the name of the positive ion – usually a metal – no changes are made to this first name. The second name will be the name of the polyatomic ion as it is – there are no changes made to the name of polyatomic ions when they are used in a compound. The second name will be the name of the polyatomic ion as it is – there are no changes made to the name of polyatomic ions when they are used in a compound. The second name – if the second part of the compound is just a nonmetal (not a polyatomic) – will be the shortened name of the nonmetal with the “IDE” ending. The second name – if the second part of the compound is just a nonmetal (not a polyatomic) – will be the shortened name of the nonmetal with the “IDE” ending. Examples: Examples: –CaSO 4 – Calcium sulfate –K 3 PO 4 – Potassium phosphate –NH 4 Cl – Ammonium chloride

Molecular Compounds Molecular compounds are those which are made of two or more nonmetals bonded together because they are sharing electrons. (Two bullies are sharing the toys!) Molecular compounds are those which are made of two or more nonmetals bonded together because they are sharing electrons. (Two bullies are sharing the toys!) Molecular compounds are also known as covalent compounds. Molecular compounds are also known as covalent compounds. Covalent compounds do not form ions so you can’t go “positive ion first & negative ion second”. This means you have to name them differently than the ionic compounds. Covalent compounds do not form ions so you can’t go “positive ion first & negative ion second”. This means you have to name them differently than the ionic compounds.

Naming Covalent Compounds The covalent compounds use only nonmetals. They still have two names just like us. The covalent compounds use only nonmetals. They still have two names just like us. Prefixes are used to show how much of each nonmetal is used to make the compound. Prefixes are used to show how much of each nonmetal is used to make the compound. The prefixes used are: The prefixes used are: Mono – 1Tetra – 4Hepta - 7 Di – 2Penta – 5Octa - 8 Tri – 3Hexa – 6Nona - 9 The first name is the name of the first nonmetal used. It will have a prefix only if there is more than one of it used. No prefix needed if there is only one of the first nonmetal. The first name is the name of the first nonmetal used. It will have a prefix only if there is more than one of it used. No prefix needed if there is only one of the first nonmetal. The second name is the name of the second nonmetal used – it will be shortened with an “IDE” ending and will have a preifx (even if there is only one of it). The second nonmetal always gets a prefix. The second name is the name of the second nonmetal used – it will be shortened with an “IDE” ending and will have a preifx (even if there is only one of it). The second nonmetal always gets a prefix. Examples: N 2 O & CCl 4 Examples: N 2 O & CCl 4 Dinitrogen monoxide & Carbon tetrachloride

This May Help… Chemical Compounds Ionic Compounds Metal + Nonmetal Straight forward (Binary) Na2S Sodium sulfide “Shifty” Metals Roman Numerals FeBr3 Iron (III) bromide Polyatomic Compounds Metal + Polyatomic Polyatomic Names stay same Ca(NO3)2 Calcium nitrate Covalent Compounds Nonmetal + Nonmetal Covalent Prefixes Used N2O3 Dinitrogen trioxide

Try Naming These Examples 1. CaBr 2 2. Na 3 N 3. FeCl 2 4. CuO 5. Be(OH) 2 6. Ca 3 (PO 4 ) 2 7. K 2 S 8. Li 2 CO 3 9. SnCl Fe(ClO 3 ) NH 4 I 12. Pb(NO 3 ) 2 1. Calcium bromide 2. Sodium nitride 3. Iron (II) chloride 4. Copper (II) oxide 5. Beryllium hydroxide 6. Calcium phosphate 7. Potassium sulfide 8. Lithium carbonate 9. Tin (IV) chloride 10. Iron (III) chlorate 11. Ammonium iodide 12. Lead (II) nitrate

THE END!