Naming Ionic Compounds

Chemical reactions occur when atoms gain, lose, or share electrons. Metals Nonmetals Nonmetals _____________ electrons. This gives them a ____ charge. Negative ions are called ___________. gain / accept _ anions Metals ________________ electrons. This gives them a ____ charge. Positive ions are called ___________. lose / donate + cations

Look for the Roman Numeral! Remember that the charge of an ion can be determined by its place on the Periodic Table. +1 +4 or -4 +2 +3 -3 -2 -1 Look for the Roman Numeral!

chlor- + -ide = chloride Rules for Naming Ions 1. The names of metals do not change. 2. Changing the name of nonmetals: root of element name + -ide = name of ion Examples: The name of chlorine’s ion: chlor- + -ide = chloride The name of nitrogen’s ion: nitr- + -ide = nitride

Examples of naming ions: The name of calcium’s ion: calcium (The names of metals don’t change!) The name of oxygen’s ion: ox- + -ide = oxide The name of aluminum’s ion: aluminum (The names of metals don’t change!)

Write the name of each of the ions on your notes. sulfide lithium nitride bromide potassium chloride oxide hydrogen (+), hydride (-)

There are also ions that form after elements have shared electrons There are also ions that form after elements have shared electrons. These ions are known as polyatomic ions, and each polyatomic ion already has a name.

Steps for Naming Ionic Compounds CaBr2 calcium bromide Step 1: Write the name of the metal ion. Step 2: Write the name of the nonmetal ion. Step 3: YOU ARE DONE! It is that easy.

1. NaF 2. MgO sodium fluoride magnesium oxide 3. SrCl2 4. Li2S strontium chloride lithium sulfide 5. CaO 6. KI calcium oxide potassium iodide

When polyatomic ions are used, simply use the name of the polyatomic ion in the compound. 1. NH4F 2. CaSO4 ammonium fluoride calcium sulfate 3. Mg(NO3)2 4. NaOH magnesium nitrate sodium hydroxide

Mg I +2 - MgI2 magnesium iodide You can also determine the formula of an ionic compound from its name. To do this, you will need to use what you already know about the Periodic Table. magnesium iodide Mg I +2 - MgI2 Step 1: Write the symbol of the metal ion. Step 2: Write the symbol of the nonmetal ion. Step 3: Determine the charges using the periodic table. Step 4: Determine the formula from the ions.

Sr NO3 +2 - Sr(NO3)2 strontium nitrate This is just as easy to do with polyatomic ions. You just need to use the name of the polyatomic ion. strontium nitrate Sr NO3 +2 - Sr(NO3)2 Step 1: Write the symbol of the metal ion. Step 2: Write the formula of the polyatomic ion. Step 3: Determine the charges using the periodic table and the table of polyatomic ions. Step 4: Determine the formula from the ions.

N-3 NO3- S-2 SO3-2 P-3 PO4-3 nitrate nitride sulfide sulfite phosphate Be very careful that you do not mix up the names of ions. This is very common for beginners to naming. Decide which name goes with each ion. nitrate N-3 NO3- nitride sulfide S-2 SO3-2 sulfite phosphate P-3 PO4-3 phosphide

We know they are positive because metals are always positive. Remember that the names of transition metals include their charge because their charges are less predictable. What are the charges of the transition metals below: Iron (II) _______ Iron (III) _______ Copper (II) _______ Copper (I) _______ Tin (IV) _______ Tin (II) _______ Lead (II) _______ Lead (IV) _______ +2 +3 +2 +1 +4 +2 +2 +4 We know they are positive because metals are always positive.

Fe O +3 -2 Fe2O3 iron (III) oxide The charges of the transition metals are important when you are determining the formula of an ionic compound. iron (III) oxide Fe O +3 -2 Fe2O3 Step 1: Write the symbol of the cation. Step 2: Write the symbol of the anion. Step 3: Determine the charges using the periodic table and the roman numerals. Step 4: Determine the formula from the ions.

SO4-2 S-2 SO3-2 N-3 NO2- NO3- Helpful Hint: If the ion ends in –ide, it is probably from the periodic table. If the ion ends in –ate or –ite, it is a polyatomic ion. Examples: sulfate sulfide sulfite SO4-2 S-2 SO3-2 nitride nitrite nitrate N-3 NO2- NO3-

Naming Binary Covalent Compounds 17

Chemical reactions occur when atoms gain, lose, or share electrons. shared electrons Nonmetals Chemical reactions occur when atoms gain, lose, or share electrons. Sharing electrons creates a covalent bond Nonmetals can _______ electrons to form a covalent bond. This creates a ___________. share molecule 18

Determining if a compound is ionic or covalent is easy. What elements do covalent compounds contain? Covalent compounds contain only nonmetals. What elements do ionic compounds contain? Ionic compounds contain a metal and a nonmetal. 19

Decide whether the compounds on your notes are ionic or covalent. 20

Important Facts: H+ H2 H- Because hydrogen only has 1 proton and 1 electron, it behaves differently than any other element on the periodic table of elements. Hydrogen can donate its 1 electron. H+ H2 Hydrogen can share electrons. Hydrogen can gain 1 electron. H- This means that hydrogen can act as either a metal or a nonmetal! 21

There are 7 elements that exist in nature as diatomic molecules. What elements exist as diatomic molecules? H2, N2, O2, F2, Cl2, Br2, I2 22

Binary Covalent Compounds There are millions of covalent compounds. These can be classified into many different types of compounds. Each type of compound has a different set of rules for naming. You will be learning about the easiest type of covalent compound to name: Binary Covalent Compounds What does binary mean? Binary means 2. Binary covalent compounds are between 2 different nonmetals. 23

phosphorous and chlorine Nonmetals can share electrons in many different ways. This means that two nonmetals can create multiple compounds together. carbon and oxygen phosphorous and chlorine CO CO2 PCl3 PCl5 nitrogen and oxygen N2O4 N2O3 Each of these contains a different ratio of elements. Because of this, we have to make sure that the name of the compound explains the correct ratio. 24

To show the correct ratio of elements, we use prefixes. 25

Binary Covalent Compounds Steps for Naming Binary Covalent Compounds N2O4 dinitrogen nitrogen tetroxide oxide Step 1: Write the name of the first nonmetal. Step 2: Write the name of the second nonmetal changing its ending to -ide. Step 3: Add prefixes to specify how many of each element are present. 26

Rules for Using Prefixes Rule 1: Prefixes are only for BINARY COVALENT compounds. Rule 2: The prefix mono- is never used on the first element of a binary covalent compound. Without a prefix it is assumed that there is only 1. Example: CO2 is carbon dioxide, and not monocarbon dioxide. Rule 3: Remove the -o or -a from a prefix before adding it to oxide. Example: CO is carbon monoxide, and not carbon monooxide. 27

How would you write each of the prefixes in front of oxide? Remember: Remove the -o or -a from a prefix before adding it to oxide. Leave -i alone. mono- ____________ di- ____________ tri- ____________ tetra- ____________ penta- ____________ hexa- ____________ hepta- ____________ octa- ____________ nona- ____________ deca- ____________ monoxide dioxide trioxide tetroxide pentoxide hexoxide heptoxide octoxide nonoxide decoxide 28

Name the binary covalent compounds that are found on your notes. carbon dioxide carbon disulfide phosphorous tribromide phosphorous pentabromide diphosphorous pentasulfide dinitrogen monosulfide silicon disulfide nitrogen tribromide dinitrogen tetrachloride 29

dinitrogen tetrafluoride Because of the prefixes, it is very easy to go from the name of a binary covalent compound to its formula. dinitrogen tetrafluoride N2 F4 Step 1: Write the symbol of the first nonmetal and the subscript that matches the prefix. Step 2: Write the symbol of the second nonmetal and the subscript that matches the prefix. 30

Write the formulas of the binary covalent compounds in your notes. CCl4 IF7 PCl5 N2O4 N2O PCl3 CS CO BH3 ICl S2Br6 S4N4 H2O SiS2 PI3 ClF5 NCl3 NO2 31

Naming Ionic and Covalent Compounds Review 32

Chemical reactions occur when atoms gain, lose, or share electrons. This is what creates compounds! Nonmetals _____________ electrons. This gives them a ____ charge. Negative ions are called ___________. gain / accept _ anions Metals ________________ electrons. This gives them a ____ charge. Positive ions are called ___________. lose / donate + cations 33

Ionic compounds contain a metal and a nonmetal. What elements do ionic compounds contain? Ionic compounds contain a metal and a nonmetal. Nonmetals Metals 34

MgCl2 Steps for Naming Ionic Compounds YOU ARE DONE! It is that easy. magnesium chloride Step 1: Write the name of the metal ion. Step 2: Write the name of the nonmetal ion. Remember that we change the name of nonmetal ions to –ide. YOU ARE DONE! It is that easy. 35

Chemical reactions occur when atoms gain, lose, or share electrons. shared electrons Nonmetals Chemical reactions occur when atoms gain, lose, or share electrons. Sharing electrons creates a covalent bond Nonmetals can _______ electrons to form a covalent bond. This creates a ___________. share molecule 36

What elements do covalent compounds contain? Covalent compounds contain only nonmetals. Nonmetals 37

Steps for Naming Covalent Compounds diphosphorous phosphorous tetrasulfide sulfide Step 1: Write the name of the first nonmetal. Step 2: Write the name of the second nonmetal changing its ending to -ide. Step 3: Add prefixes to specify how many of each element are present. 38

Rules for Using Prefixes with Covalent Compounds Rule 1: Prefixes are only for COVALENT compounds. Rule 2: The prefix mono- is never used on the first element of a binary covalent compound. Without a prefix it is assumed that there is only 1. Example: PCl3 is phosphorous trichloride, and not monophosphorous trichloride. Rule 3: Remove the -o or -a from a prefix before adding it to oxide. Example: N2O4 is nitrogen tetroxide, and not nitrogen tetraoxide. 39

Determining if a compound is ionic or covalent is easy. What elements do ionic compounds contain? Ionic compounds contain a metal and a nonmetal. What elements do covalent compounds contain? Covalent compounds contain only nonmetals. 40

Decide whether the compounds on your notes are ionic or covalent. 41

Only COVALENT COMPOUNDS use PREFIXES! Once you decide if a compound is ionic or covalent you know whether or not to use prefixes. Only COVALENT COMPOUNDS use PREFIXES! Do NOT make the mistake of using prefixes with ionic compounds. You will be forced to decide between answer choices with and without prefixes on your exam. Know the difference! 42

Steps for Naming a Compound Step 1: Decide if the compound is ionic or covalent. Step 2: Write the name of the first element as it appears on the periodic table, change the name of the second element to end with -ide. Ionic compounds are finished at this point. Step 3: If, and only if, the compound is covalent, add prefixes. 43

Remember, if polyatomic ions appear in an ionic compound, simply use the name of the ion as it appears in the table of polyatomic ions. 1. NH4Cl 2. MgSO3 ammonium chloride magnesium sulfite 3. Ca(NO2)2 4. KOH calcium nitrite potassium hydroxide 44

Write the names of the compounds that appear on your notes. carbon tetrabromide carbon monosulfide sodium permanganate strontium iodide potassium sulfate dinitrogen tetrasulfide magnesium nitrate silicon tetrachloride diphosphorous pentoxide 45

Determining the Formula of an Ionic Compound from Its Name potassium sulfide K S + -2 K2S Step 1: Write the symbol of the metal ion. Step 2: Write the symbol of the nonmetal ion. Step 3: Determine the charges using the periodic table. Step 4: Determine the formula from the ions. 46

The charges are the same, so they cancel! This is just as easy to do with polyatomic ions. You just need to use the table of polyatomic ions found on the naming compounds reference sheet. barium sulfate The charges are the same, so they cancel! Ba SO4 +2 -2 BaSO4 Step 1: Write the symbol of the metal ion. Step 2: Write the formula of the polyatomic ion. Step 3: Determine the charges using the periodic table and the table of polyatomic ions. Step 4: Determine the formula from the ions. 47

S-2 SO4-2 P-3 PO4-3 N-3 NO2- sulfide sulfate phosphate phosphide Be very careful that you do not mix up the names of ions. This is very common for beginners to naming. Decide which name goes with each ion. sulfide S-2 SO4-2 sulfate phosphate P-3 PO4-3 phosphide nitrite N-3 NO2- nitride 48

We know they are positive because metals are always positive. Remember that the names of transition metals include their charge because their charges are less predictable. What are the charges of the transition metals below: d-block Tin (IV) _______ Tin (II) _______ Lead (II) _______ Lead (IV) _______ Iron (II) _______ Iron (III) _______ Copper (II) _______ Copper (I) _______ +4 +2 +4 +2 +2 +3 +2 +1 We know they are positive because metals are always positive. 49

Cu NO3 +2 - Cu(NO3)2 copper (II) nitrate The charges of the transition metals are important when you are determining the formula of an ionic compound. copper (II) nitrate Cu NO3 +2 - Cu(NO3)2 Step 1: Write the symbol of the metal ion. Step 2: Write the symbol of the polyatomic ion. Step 3: Determine the charges using the periodic table, polyatomic ions table, or the roman numerals. Step 4: Determine the formula from the ions. 50

Because of the prefixes, it is very easy to go from the name of a binary covalent compound to its formula. dihydrogen monoxide H2 O Step 1: Write the symbol of the first nonmetal and the subscript that matches the prefix. Step 2: Write the symbol of the second nonmetal and the subscript that matches the prefix. 51

Example: carbon dioxide Remember: The prefix mono- is never used on the first element of a binary covalent compound. Without a prefix it is assumed that there is only 1. Example: carbon dioxide CO2 52

Write the formulas of the compounds that appear on your notes based on their names. HCl BaF2 SnS N2O CS2 S2Cl6 Na3PO4 PtCl2 53