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Chemistry IANB Page 11

Chemistry IANB Page 11. READ: Chemical Bonds DO: Ion notation review Ionic Bonds Chemical Formulas of Binary Compounds Ionic Compounds. Chemical Bonds and Compounds. Two types of bonds in compounds. IONIC COVALENT. Table of the Elements. 1. 8. 3 4 5 6 7. 2.

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Chemistry IANB Page 11

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  1. ChemistryIANB Page 11 READ: Chemical Bonds DO:Ionnotation review Ionic Bonds Chemical Formulas of Binary Compounds Ionic Compounds

  2. Chemical Bonds and Compounds Two types of bonds in compounds. IONIC COVALENT

  3. Table of the Elements 1 8 3 4 5 6 7 2 Determine the Type of Chemical Bond • One method is to look at the type of element that is reacting. When nonmetals bond with each other, Covalent Bonds tend to form. Metals and Nonmetals have different pulls on their electrons. The stronger nonmetals will take electrons from the weaker metals forming Ionic Bonds When Metals react with Nonmetals, Ionic Bonds tend to form Nonmetals tend to have a similar pull on their electrons, so they will share electrons and form covalent bonds. Nonmetals Metals

  4. Electronegativities of the Elements 1 8 3 4 5 6 7 2 Determine the Type of Chemical Bond • A second method is to look at the positions on the Periodic Table of elements that are reacting. Atoms that are close together on the Periodic Table tend to form Covalent Bonds Atoms that are far apart on the Periodic Table have a bigger difference tend to form Ionic Bonds

  5. Chemical Bonds – Ionic Bond +1 -1 Cl Na Cl Na Ionic Bonds Opposite charges attract.The positive Sodium Ion is pulled toward the negative Chlorine Ion. Sodium is now a positively charged ion: Na+1Chlorine is now a negatively charged ion: Cl -1 Notice: The electron was completelyExchanged from the sodium to the chlorine. The attraction that holds the positive ion to the negative ion is called an Ionic Bond. Sodium wants to give up its outer electron.Chlorine wants to getanother electron. Sodium Chloride is an Ionically bonded substance. It is formed from a Sodium atom and a Chlorine atom. The ionic compound that is the result of the transfer of eletrons is held together with an Ionic Bond. Sodium is a highly reactive metal. If you were to put it in water it would explode. Sodium has 1 electron in its outer energy level.Chlorine has 7 electrons in itsouter energy level. We have created a a new substance the ionic compound: Sodium Chloride. Chlorine is a highly reactive nonmetal. It is extremely poisonous, even deadly, if it is inhaled. This shows the importance of chemical reactions and chemical bonds. But with the exchange of a single electron, we have created the ionic compound that is ordinary table salt. -1 +1 Sodium ChlorideNaCl Sodium Chlorine

  6. Ionic Bonds with Lewis Models Ions formed Electron transfer

  7. Formation of Ionic BondsElectron is transferred from metal (group 1) to nonmetal (group 17)creating a Cation (1+) and an Anion (1-) Ionic substances or Salts Usually solids with very high melting points. Usually dissolve in water. Bohr Model Lewis Model

  8. Formation of Ionic BondsGroup 1 metal and Group 17 nonmetal The transfer of one electron produces ions. The opposite electric charge of the ions creates an attraction that is the ionic bond. Ionic bonding occurs between metals and non-metals Ions result Transfer of e-

  9. Formation of Ionic BondsGroup 2 metal and Group 17 nonmetal – Mg2+ Cation and 2 Cl1- Anions The transfer of two electrons from Mg to two Cl produces three ions in the ratio MgCl2 Ionic compounds of a metal and nonmetal are called salts

  10. Formation of Ionic BondsGroup 2 metal and Group 17 nonmetal – Mg2+ Cation and 2 Cl1- Anions Formation of CaBr2 1- • • • • • • • Ca Br • • • + Br • • • • • • • Ca2+ + • • • • Br 1- • • • • • • • Br • • • •

  11. IANB Page 11Complete Ionic bonds – bonds of attraction

  12. Chemical Formulas The type of element is expressed by the chemical symbol of the element. You know that the compound NaCl is composed of Sodium and Chlorine because the chemical formula includes both of their symbols. Symbol for Sodium Symbol for Chlorine 1 of 8 Home • A Chemical Formula tells which elements make up a compound and how many atoms of each element are needed to make a single molecule. NaCl

  13. Chemical Formulas SodiumMetal MagnesiumMetal CarbonNonmetal ChlorineNonmetal OxygenNonmetal OxygenNonmetal 2 of 8 • The more metallic element is written first in a chemical formula. NaCl MgO CO Although Carbon is a nonmetal, it is to the left of Oxygen on the Periodic Table which makes it more metallic than Oxygen.

  14. Subscript 3 of 8 Chemical Formulas • The subscript tells you the number of atoms that are bonded together to make one molecule. MgCl2 The subscript 2 tells us that there are two Chlorine ions involved in bonds to make a molecule of Magnesium Chloride. There is no subscript on the Magnesium ion. This is because there is only one Magnesium ion in this molecule. Subscripts of 1 are not written out. This formula tells us that one molecule of Magnesium Chloride is composed of1 Magnesium bonded to 2 Chlorines.

  15. Chemical Formulas 4 of 8 • What do the following chemical formulas tell you? NaCl = 1 Sodium bonded to 1 Chlorine Li2S = 2 Lithiums bonded to 1 Sulfur Fe2O3 = 2 Irons bonded to 3 Oxygens

  16. Chemical Formulas 5 of 8 • Subscripts are extremely important in a chemical formula because they determine the compound. CO2 is the formula for Carbon Dioxide.A molecule with 1 Carbon bonded to 2 Oxygens.Carbon Dioxide is the gas you exhale all day long. CO2 CO is the formula for Carbon Monoxide.A molecule with 1 Carbon bonded to 1 Oxygen.Carbon Monoxide is a deadly gas in your car’s exhaust. CO When you change the subscript, you change the number of atoms involved in bonds to make the molecule and therefore you change the compound.CO2 and CO are two different compounds.

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  18. Na Cl Determine Formulas for Simple Salts • Remember, atoms can’t take electrons unless they can find someone to give. Atoms can’t give electrons unless they can find someone to take. Na Cl +1 -1 Sodium, from Group 1, has 1 electron in its outer energy level. Chlorine, from Group 7, has 7 electrons in its outer energy level. Sodium wants to give one electron. Chlorine wants to take one electron. Since sodium wants to give one electron and chlorine wants to take one electron, a molecule of Sodium Chloride is made up of one sodium bonded to one chlorine. We can get the same information by looking at the charges the atoms take on after they react. These charges are sometimes called the valence or the oxidation number and they result from a gain or loss of electrons. Sodium in Group 1 takes on a +1 charge.Chlorine in Group 7 takes on a –1 charge. A molecule, by definition, must have an overall charge of Zero.This means all the positive charges must equal all the negative charges.(electrons lost = electrons gained) One sodium atom with a +1 charge balances out one chlorine atom with a –1 charge.So, a molecule of sodium chloride has one sodium atom bonded to one chlorine atom and an overall charge of zero.

  19. Determine Formulas for Simple Salts • Write the chemical formula for Lithium Sulfide. +1 +1 -2 Li Li S Li2S One Sulfur has a -2 charge but one Lithium has only a +1 charge. So…To make a molecule with an overall charge of zero we need another positive charge.That means we need another lithium atom. The name of the molecule is Lithium Sulfide.So we know there must be at least one Lithium atom and at least one Sulfur atom. Lithium in Group 1 takes on a +1 charge.(Lithium wants to give 1e-)Sulfur in Group 6 takes on a –2 charge.(Sulfur wants to get 2 e-)Will one lithium react with one sulfur? The formula for Lithium Sulfide is Li2S.It takes two Lithiums to balance out one Sulfur for an overall charge of zero.Notice: the charges on the atoms are not included in the chemical formula.

  20. Determine Formulas for Simple Salts • Write the chemical formula for Calcium Chloride. +2 -1 -1 Ca Cl Cl CaCl2 One Calcium has a +2 charge but one Chlorine has only a -1 charge. So…To make a molecule with an overall charge of zero we need another negative charge.That means we need another chlorine atom. The name of the molecule is Calcium Chloride.So we know there must be at least one Calcium atom and at least one Chlorine atom. Calcium in Group 2 takes on a +2 charge.(Calcium wants to give 2e-)Chlorine in Group 7 takes on a –1 charge.(Chlorine want to get 1 e-)Will one Calcium react with one Chlorine? The formula for Calcium Chloride is CaCl2.It takes two Chlorines to balance out one Calcium for an overall charge of zero.Notice: the charges on the atoms are not included in the chemical formula.

  21. IONIC BONDING PRACTICEPage 10 IANB Complete the table now by writing the formula of the compound formed by the ions given. Remember the resulting Compound is neutral. IONS Li3N LiCl Li2S Ca3N2 CaCl2 CaS Al2S3 AlN AlCl3

  22. IANB p 54 Determine Formulas for Simple Salts – Ionic Bonds • Write the chemical formulas for the following salts then click for the answers. IANB P10 NaBr K2S BeO CaBr2 Li2O Cs2O BaF2 SrCl2

  23. Chloride 10 of 12 Determine Formulas for Simple Salts – Ionic Bonds • Determine the name of the following salt: NaCl Sodium Chlorine That’s it! Naming is easy for salts that are composed of metals from Groups 1 & 2.That’s because these metals react the same way every time. Sodium always gives up one electron.Chlorine will accept one electron.So, sodium and chlorine will only react with each other in a 1 to 1 ratio. The name Sodium Chloride says it all. Write the name of the nonmetal with the suffix - ide This molecule is composed of two different elements: Sodium & Chlorine.Write the name of the metal atom first.

  24. Chloride 11 of 12 Determine Formulas for Simple Salts – Ionic Bonds • Determine the name of the following salt: CaCl2 Calcium Chlorine That’s it! Naming is easy for salts that are composed of metals from Groups 1 & 2.That’s because these metals react the same way every time. Calcium always gives up two electrons.Chlorine will accept one electron.So, calcium and chlorine will only react with each other in a 1 to 2 ratio. The name Calcium Chloride says it all. Write the name of the nonmetal with the suffix - ide This molecule is composed of two different elements: Calcium & Chlorine.Write the name of the metal atom first.

  25. 12 of 12 Determine Formulas for Simple Salts – Ionic Bonds Home • Write the name of the salt given the chemical formula then click for the answers. IANB P10 Potassium Oxide Sodium Fluoride Magnesium Oxide Beryllium Iodide Barium Bromide Lithium Sulfide

  26. Determine Formulas for Simple Salts – Ionic Bonds • Write the chemical formulas for the following salts then click for the answers. NaBr K2S BeO CaBr2 Li2O Cs2O BaF2 SrCl2

  27. Home Salts with Multivalent Metals • Group 1 metals lose 1e- and take on a +1 charge.Group 2 metals lose 2e- and take on a +2 charge. • But, what about all the other metals? What will they do when they react and form salts? • Other metals can give different numbers of electrons in different situations. Iron can give 2e- or 3e- and take on a +2 or +3 charge. • Elements that can react differently in different situations are called multivalent.

  28. Charge on eachremaining atom Charge on one Bromine Total positive chargeto balance out -3 Charge on all 3 Bromines 1 of 4 Salts with Multivalent Metals • Determine the charge on the nickel in the compound NiBr3. Overall Charge = Zero + 3 - 1 Ni Br3 Bromine takes 1 e- + 3 - 3 Step 3: Balance out the total negative charges with positive charges.We have 3 negative charges total. The charge on the whole atom is zero. So, we must have 3 positive charges. Step 4: Distribute the positive charges to the remaining atoms.We have 3 positive charges and only 1 nickel so all three positive charges must have come from the one nickel. With these two pieces of information we can begin to determine the charge on nickel in this compound. The nickel ion, in this particular compound NiBr3,must have a positive 3 charge. Nickel is a metal so it will give e-. That means bromine must take electrons.Bromine is in Group 7 so it will probably take 1 electron. Second: We don’t know how nickel reacted but we do know how bromine reacted. Step2: Write the total charge on all of the bromines in this molecule.There are 3 bromines in this molecule. One bromine is -1. So, three are –3. Step1: Write the charge on one of the atoms in which you have the most confidence (Bromine in this case).The charge on one Bromine = -1 First: NiBr3 is a molecule and by definition a molecule must have an overall charge of zero Since Nickel is not in Group 1 or 2, we can’t be immediately sure of its charge. But, we have some information that will help us figure it out.

  29. Charge on eachremaining atom Charge on one Oxygen Total positive chargeto balance out -2 Charge on all the Oxygens 2 of 4 Salts with Multivalent Metals • Determine the charge on one copper in the compound Cu2O. Overall Charge = Zero + 1 - 2 Cu2 O Oxygen takes 2 e- + 2 - 2 Step 3: Balance out the total negative charges with positive charges.We have 2 negative charges total. The charge on the whole atom is zero. So, we must have 2 positive charges. Step 4: Distribute the positive charges to the remaining atoms.We have 2 positive charges and two coppers so each copper must be +1 Each copper, in this particular compound, Cu2O,,must have a positive 1 charge. With these two pieces of information we can begin to determine the charge on copper in this compound. Copper is a metal so it will give e-. That means oxygen must take e-.Oxygen is in Group 6 so it will take 2 electrons. Second: We don’t know how copper reacted but we do know how oxygen reacted. Step2: Write the total charge on all of the oxygens in this molecule.There is only one oxygen in this molecule. One oxygen is -2. Step1: Write the charge on one of the atoms in which you have the most confidence (Oxygen in this case).The charge on one Oxygen = -2 First: Cu2O is a molecule and by definition a molecule must have an overall charge of zero Since copper is not in Group 1 or 2, we can’t be immediately sure of its charge. But, we have some information that will help us figure it out.

  30. Charge on eachremaining atom Charge on one Fluorine Total positive chargeto balance out -1 Charge on all the Fluorines 3 of 4 Salts with Multivalent Metals • Determine the charge on the silver in the compound AgF. Overall Charge = Zero + 1 - 1 Ag F Fluorine takes 1 e- + 1 - 1 Step 3: Balance out the total negative charges with positive charges.We have 1 negative charge total. The charge on the whole atom is zero. So, we must have 1 positive charge. Each silver, in this particular compound, AgF,,must have a positive 1 charge. Step 4: Distribute the positive charges to the remaining atoms.We have 1 positive charge and one silver so that silver must be +1 With these two pieces of information we can begin to determine the charge on silver in this compound. Silver is a metal so it will give e-. That means fluorine must take e-.Fluorine is in Group 7 so it will take 1 electron. Second: We don’t know how silver reacted but we do know how fluorine reacted. Step2: Write the total charge on all of the fluorines in this molecule.There is only one fluorine in this molecule. One fluorine is -1. Step1: Write the charge on one of the atoms in which you have the most confidence (Fluorine in this case).The charge on one Fluorine = -1 First: AgF is a molecule and by definition a molecule must have an overall charge of zero Since silver is not in Group 1 or 2, we can’t be immediately sure of its charge. But, we have some information that will help us figure it out.

  31. Charge on eachremaining atom Charge on one Sulfur Total positive chargeto balance out -6 Charge on all 3 Sulfurs 4 of 4 Salts with Multivalent Metals • Determine the charge on one iron in the compound Fe2S3. Overall Charge = Zero + 3 - 2 Fe2 S3 Sulfur takes 2 e- + 6 - 6 Step 3: Balance out the total negative charges with positive charges.We have 6 negative charges total. The charge on the whole atom is zero. So, we must have 6 positive charges. Step 4: Distribute the positive charges to the remaining atoms.We have 6 positive charges and two irons so each iron must be +3 Each iron, in this particular compound Fe2S3,must have a positive 3 charge. With these two pieces of information we can begin to determine the charge on iron in this compound. Iron is a metal so it will give e-. That means sulfur must take electrons.Sulfur is in Group 6 so it will probably take 2 electrons. Second: We don’t know how iron reacted but we do know how sulfur reacted. Step2: Write the total charge on all of the sulfurs in this molecule.There are 3 sulfurs in this molecule. One sulfur is -2. So, three are –6. Step1: Write the charge on one of the atoms in which you have the most confidence (Sulfur in this case).The charge on one Sulfur = -2 First: Fe2S3 is a molecule and by definition a molecule must have an overall charge of zero Since Iron is not in Group 1 or 2, we can’t be immediately sure of its charge. But, we have some information that will help us figure it out.

  32. 8 of 13 Salts with Multivalent Metals • Determine the charge on one of the metal atoms in salts listed below. Li = +1 Co = +3 Mn = +3 Sn = +2 Hg = +1 Cu = +1 Pb = +4 Cr = +6

  33. 10 of 13 Salts with Multivalent Metals • Let’s name two salts that are composed of a multivalent metal. - 2 + 2 - 2 + 3 Fe2 O3 Fe O + 2 - 2 - 6 + 6 Iron Oxide III Iron Oxide II Remember: The overall charge on a molecule is zero.Start with the atom in which you have the most confidence. Oxygen in Group 6 is -2 Each iron atom in the second molecule has a +2 Charge.This molecule is called Iron II Oxide(say: iron two oxide) Step 2: Write the total charge on all the Oxygens.1st Molecule  3 Oxygens each is –22nd Molecule  1 Oxygen which is -2 To properly name these two compounds, we have to know the form of the metal.In other words, we have to find the charge on one metal atom in each compound. We can’t call both compounds Iron Oxide because they are two different compounds with different formulas. Step 3: Balance out the total negative charges with an equal number of positive charges. The overall charge on a molecule is zero Step 4: Divide the total positive charge among the metal atoms.1st Molecule  2 Fe 2nd Molecule  1Fe The rest of the names for these two molecules is determined by the charge on the metal. Each iron atom in the first molecule has a +3 Charge.This molecule is called Iron III Oxide(say: iron three oxide) Step 1: Write the charge on one Oxygen.Oxygen from Group 6 wants 2 electrons so it will take on a –2 charge. Both of these salts are composed of Iron (Fe) and Oxygen (O).

  34. 11 of 13 Name Salts with Multivalent Metals • Let’s name two salts that are composed of a multivalent metal. - 1 + 2 - 2 + 1 Cu2 S Cu Cl2 + 2 - 2 - 2 + 2 Copper Sulfide I Copper Chloride II Remember: The overall charge on a molecule is zero.Start with the atom in which you have the most confidence. Sulfur = -2 Chlorine = -1 Each copper atom in the second molecule has a +2 Charge.This molecule is called Copper II Chloride(say: copper two chloride) Step 2: Write the total charge on all the nonmetals.1st Molecule  1 Sulfur which is –22nd Molecule  2 Chlorines each is -1 To properly name these two compounds, we have to know the form of the metal.In other words, we have to find the charge on a copper atom in each compound. We can’t just call these compounds Copper Sulfide and Copper Chloride because we don’t know which form of copper is in which molecule. Step 3: Balance out the total negative charges with an equal number of positive charges. The overall charge on a molecule is zero Step 4: Divide the total positive charge among the metal atoms.1st Molecule  2 Cu 2nd Molecule  1Cu Both of these salts are composed of Copper (Cu). One combines with Sulfur (S). The other combines with Chlorine (Cl). The rest of the names for these two molecules is determined by the charge on the metal. Each Copper atom in the first molecule has a +1 Charge.This molecule is called Copper I Sulfide(say: copper one sulfide) Step 1: Write the charge on 1 Sulfur & 1 Chlorine.Sulfur (Group 6) wants 2 e-  –2 charge.Chlorine (Group 7) wants 1 e-  -1 charge.

  35. 12 of 13 Salts with Multivalent Metals • Write the name of the salt given the chemical formula then click for the answers. (Remember to check charge on the metal). Tin II Fluoride Nickel IIIBromide Gold IOxide Gold IIISulfide Lead IV Sulfide Chromium VIOxide Mercury IIChloride Manganese VIIOxide

  36. 2 of 14 Salts with Polyatomic Ions • Let’s look at the term Polyatomic Ion. “Poly-” means Many “-Atomic” refers to atoms “Ion” means Has a Charge • A Polyatomic Ion is two or more atoms that are covalently bonded together that have a charge. • The next slide contains some examples of polyatomic ions. It includes the formula, the charge, and the name.

  37. 3 of 14 Salts with Polyatomic Ions • Common Polyatomic Ions

  38. 4 of 14 Salts withPolyatomic Ions • Polyatomic Ions can bond with other atoms to form molecules. • Notice, most of the polyatomic ions have negative charges and are composed of nonmetals. • These negative polyatomic ions often form bonds with positive metal ions creating molecules that we will classify as salts. • These salts are generally held together with ionic bonds while the polyatomic ions themselves are held together with covalent bonds.

  39. 5 of 14 Salts with Polyatomic Ions • Write the formula for Calcium Sulfate. +2 -2 Ca SO4 CaSO4 Calcium in Group 2 takes on a +2 charge.The Sulfate ion always has a –2 charge. One calcium with a +2 charge balances out one sulfate ion with a –2 charge.So, a molecule of Calcium Sulfate has one Calcium ion bonded to one Sulfate ion The formula for Calcium Sulfate is CaSO4.One Calcium balances out one Sulfate for an overall charge of zero.Notice: the charges on the ions are not included in the chemical formula. How did we know that the formula for Calcium Sulfate was CaSO4 and not CaS.CaS is Calcium Sulfide. Polyatomic ions generally have names that end with something other than –ide. You can usually recognize the name of a polyatomic ion because it ends with -ate, -ite, -ium.One exception is the Hydroxide Ion OH-1. We will discuss this ion later. We know what Calcium means in Calcium Sulfate, but what does Sulfate stand for?Sulfate is the name of a polyatomic ion.SO4-2 The name of the molecule is Calcium Sulfate.So we know there must be at least one Calcium atom.

  40. 6 of 14 Salts with Polyatomic Ions • Write the formula for Lithium Carbonate. +1 +1 -2 Li Li CO3 Li2CO3 The name of the molecule is Lithium Carbonate.So we know there must be at least one Lithium atom and at least one Carbonate ion (CO3-2). Lithium in Group 1 takes on a +1 charge.(Lithium wants to give 1e-)Carbonate is the name of a polyatomic ion(CO3) that always has a –2 charge.Will one lithium react with one Carbonate? One Carbonate ion has a -2 charge but one Lithium has only a +1 charge. So…To make a molecule with an overall charge of zero we need another positive charge.That means we need another lithium. Lithium Carbonate has the formula Li2CO3.It takes two Lithiums to balance out one Carbonate for an overall charge of zero.Note: Carbonate refers to the CO3-2 ion Carbonide would refer to plain Carbon (C)

  41. 7 of 14 Salts with Polyatomic Ions • Write the chemical formula for Copper II Nitrate. +2 -1 -1 Cu NO3 NO3 ( ) Cu NO3 2 One Copper has a +2 charge but one Nitrate has only a -1 charge. So…To make a molecule with an overall charge of zero we need another negative charge.That means we need another Nitrate Ion. The fact that it is Copper II tells us that we are dealing with Copper with a +2 charge.Nitrate (NO3) is a polyatomic ion that always has a –1 charge.Will one Copper react with one Nitrate? The name of the molecule is Copper II Nitrate.So we know there must be at least one Copper atom and at least one Nitrate ion (NO3-1) . Copper II Nitrate is Cu(NO3)2.It takes two nitrate ions to balance out one Copper for an overall charge of zero.Notice: The nitrate ion is put in parentheses with the subscript behind. Why? It is written this way to show that we are involving two nitrate groups. The parentheses show that the subscript goes with the entire polyatomic ion not just with the atom directly in front of it.

  42. 8 of 14 Salts with Polyatomic Ions • Write the chemical formula for Iron II Phosphate. +2 -3 -3 +2 +2 +6 -6 Fe Fe Fe PO4 PO4 ( ) Fe PO4 3 2 It is written this way to show that we are involving two phosphate groups and three iron ions. The parentheses show that the subscript goes with the entire polyatomic ion not just with the atom directly in front of it. Iron II Phosphate is Fe3(PO4)2.It takes three Irons to balance two Phosphate ions for an overall charge of zero.Notice: The phosphate ion is put in parentheses but the iron isn’t. Why? Since it won’t balance using only one Phosphate ion (PO4-3), try two phosphates. Two phosphate ions (PO4-3) will give you a total of 6 negative charges. Can you balance out a –6 with Fe+2 ions? You can you balance six negative charges with three with Fe+2 ions which equals +6.This makes the charge on the whole molecule equal to zero. One Iron has a +2 charge but one Phosphate has a -3 charge. So…To make a molecule with an overall charge of zero, we need more ions of each type. In cases like these, look at the ion with the larger charge (PO4-3). One phosphate has a –3 charge. You can’t balance that out with Fe+2 ions. One isn’t enough two is too many. So… The fact that it is Iron II tells us that we are dealing with Iron with a +2 charge.Phosphate (PO4) is a polyatomic ion that always has a –3 charge.Will one Iron react with one Phosphate? The name of the molecule is Iron II Phosphate.So we know there must be at least one Iron atom and at least one Phosphate ion (PO4-3) .

  43. 9 of 14 Salts with Polyatomic Ions • Write the chemical formulas for the following compounds then click for the answers. Cr(NO3)6 LiHCO3 K2SO4 Co3(PO4)2 Ni2(CO3)3 Be(NO2)2 Ca(C2H3O2)2 Sn3(PO4)4

  44. 10 of 14 Salts with Polyatomic Ions • You have been writing chemical formulas for salts composed of polyatomic ions. • Next you will write the names of these salts when given the chemical formula. • The good news is that most of the rules you learned to this point still apply. • Name the most metallic element first • If the metal is mulitvalent, its charge will be in the name. • The difference is that the nonmetal+ide ending is replaced by the name of the polyatomic ion.

  45. 11 of 14 Salts with Polyatomic Ions • Name of the following salt: Mg(NO3)2 Magnesium Nitrate Magnesium always gives up 2 electrons.It always has a –2 charge.The Nitrate ion always has a –1 charge.Since the charges are always the same, there is no reason to include them in the name That’s it! Naming is simple for salts that are composed of metals from Groups 1 & 2.That’s because these metals react the same way every time. Write the name of the Polyatomic Ion This molecule is composed of Magnesium & Nitrate ions.Write the name of the metal atom first.

  46. 12 of 14 Salts with Polyatomic Ions • Name the following salt: Cu3(PO4)2 - 3 + 2 Cu3 (PO4)2 - 6 + 6 Copper Phosphate II Remember: The overall charge on a molecule is zero.Start with the atom in which you have the most confidence. PO4 has a –3 charge Step 2: Write the total charge on all the PhosphatesThere are two phosphates each has a –3 charge which gives a total of -6 To properly name this compound, we have to know the form of the metal.In other words, we have to find the charge on one copper atom in this compound. Step 3: Balance out the total negative charges with an equal number of positive charges. The overall charge on a molecule is zero We can’t just call this compound Copper Phosphate because Copper is one of those unpredictable metals. Step 4: Divide the total positive charge among the metal atoms.There are three copper ions. The rest of the name for this molecule is determined by the charge on the metal. Each Copper atom has a +2 Charge.This molecule is Copper II Phosphate(say: copper two phosphate) Step 1: Write the charge on one Phosphate.The Phosphate ion always has a negative three charge This salt is composed ofCopper (Cu) and Phosphate ions (PO4-3).

  47. 13 of 14 Salts with Polyatomic Ions • Write the name of the salt given the chemical formula then click for the answers. (Remember to check charge on the metal). Barium Nitrite Sodium Acetate Gold IIISulfate Copper INitrate Tin IV Phosphate Chromium VICarbonate Mercury IIBicarbonate Manganese VIISulfate

  48. Chemistry You have Completed Ionic Bonding & Chemical Formulas of Binary Salts Adapted by Vern Ogle from John W. Pluemer

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