NOMENCLATURE OF BINARY POLY-ATOMIC COMPOUNDS

Giving names to chemical compounds, formulae, common polyatomic atoms. introduction about binary compounds, ionic bonds. provided with examples of binary ionic compounds.

1. N omenclature of chemical compounds, formulae, common polyatomic atoms

2. 2 Chemical reactions occur when atoms gain, lose, or share electrons . METALS NON-METALS

3. Binary compounds A substance composed of exactly two different elements, which are substances that cannot be simplified further by chemical means. 3

4. Ionic Bonds On the periodic table, strong electron donors are on the left side (alkali metals). Strong electron acceptors are on the right side (halogens). The further apart two elements are on the periodic table, the more likely they are to form an ionic compound. 4

5. Naming compounds with ionic bonds 5

6. Binary ionic - metal ion – nonmetal ion Binary molecular - two nonmetals Ternary ionic - at least one ion is a polyatomic ion Binary acid - H – nonmetal Ternary acid - H – Polyatomic ion Base - metal ion – OH TYPES OF BINARY COMPOUNDS 6

7. T ips to remember Always keep your Periodic Table handy – You should have it in front of you ALWAYS when you are naming and writing formulas. Remember that metals (except Hydrogen) are found to the left of the stair step on the Periodic Table. Nonmetals are found on the right side of the stair step of the Periodic Table. Metalloids are the 6 elements on or below the stair step except Al, Po and At. For naming purposes they will tend to behave like nonmetals.

8. NAMING BINARY COMPOUNDS A binary ionic compound is held together by ionic bonds. Binary molecular compounds consist of covalently bonded atoms. Each type of compound has its own naming rules. 8

9. How Do You Name Binary Ionic Compounds? (Composed Of Two Elements – A Metal And A Nonmetal ) Name the first ion -From groups 1, 2, 3, 13, zinc, cadmium, or silver. Name the second ion changing to suffix –ide. 9

10. NAMING BINARY IONIC COMPOUNDS 10 MgBr 2 is magnesium (name of first element) + brom (root name of second element) + i de suffix = magnesium bromide

11. Name the metal ion & the non-metal ion? CaO – calcium oxide NaCl – sodium chloride Al 2 S 3 – aluminum sulfide MgI 2 – magnesium iodide 11

12. The Transition Metals And Roman Numerals Notice – metal and nonmetal. Name the first ion. Since the first ion is a transition element , you must use a Roman Numeral to represent the charge. H ow do you know the charge? All compounds are neutral. Oxygen has a -2 charge (group 16) Therefore, iron must have a +2 charge since there is one iron and one oxygen. Iron gets a Roman Numeral (II). 12 Let’s see FeO (Ferrous II Oxide)

13. Cu 2 S – Copper (I) Sulfide Name the first ion. Since it is a transition metal, you must use a Roman Numeral. Which Roman Numeral? The Roman Numeral is the same as the charge of the ion. How do you find the charge? All compounds are neutral Sulfur has a -2 charge (group 16) There are two coppers Therefore each copper must have a +1 charge for the compound to be neutral 13

14. MnO 2 - Magnesium (IV) Oxide Name the first ion. Since it is a transition metal, you must use a Roman Numeral. How do you determine the Roman Numeral? It is the same as the charge . What is the charge of Mn? Oxygen (group 16) has a -2 charge and a total of -4 charge. There are two oxygens with one manganese. Therefore Mn must have a +4 charge for this compound to be neutral. 14

15. Why Use Roman Numerals With Transition Elements? The metals in groups 1, 2, 3, and 13 have single, definite charges. Group 1 metals have a +1 charge. Group 2 metals have a +2 charge. Groups 3 and 13 metals have a +3 charge. Transition metals may have multiple charges – usually two different positive charges. - For example, there are two copper oxide compounds : Cu 2 O & CuO - Which one of these is Copper oxide ? We must distinguish these by using a Roman Numeral . - Cu 2 O - Copper (II) oxide : Copper is + 2 - CuO - Copper (I ) oxide :Copper is +1 15

16. Three Transition Elements Which Do Not Require A Roman Numeral Because They Have Single Definite Charges . These Are: Zinc – Zn 2+ Cadmium – Cd 2+ Silver – Ag + You need to remember the charges for these. Ag 2 O - Silver Oxide ZnCl 2 - Zinc Chloride 16

17. Formulas For Binary Ionic Compounds Given The Name? 17 Magnesium chloride Mg 2+ Cl - Write the symbol and charge of each ion. Balance the charges by supplying subscripts. Subscripts tell how many of each atom is present. You need a second Cl -1 to balance the charges

18. 18 Iron (III) bromide Write the symbol and charge of each ion. The charge of the iron is provided by the Roman Numeral. Fe 3+ Br - Balance the charges by supplying subscripts. The subscripts tell how many of each ion is needed to balance the compound. You’ll need three bromine ions to balance the one iron. FeBr 3

19. 19 Aluminum Sulfide Write the symbol and charge of each ion. Al 3+ S 2- Balance the charges by supplying subscripts. In this case the charges do not evenly divide into each other. You must find the least common multiple. SIX How many aluminums are needed to arrive at a +6 charge? How many sulfurs are needed to arrive at a -6 charge? 2 3 Al 2 S 3

20. Writing Formulas a Little Quicker Iron and oxygen combine to form a compound. Iron (Fe) has an oxidation number of 3+. Oxygen (O) has an oxidation number of 2–. Predict the chemical formula of this compound. 20

21. 21 Fe 3+ O 2- 3 2 Writing Formulas a Little Quicker Simply cross the oxidation numbers and make them positive

22. 22 Mn 4+ 3- 4 3 Manganese (IV) phosphide Mn 4+ O 2- 4 2 Manganese (IV) oxide MnO 2 Cross but in this case they must be dropped! P MnP

23. Molecular Binary Compounds What are Binary Molecular Compounds? These compounds contain two elements (binary). The term “molecular” indicates that these elements are joined by a covalent bond. They must therefore be non-metals . Bottom line – 2 elements – both non-metals To name and write formulas for these, you must know some numerical prefixes. 23

24. Naming – You Must Use Prefixes. 1 = mono 3 = tri 5 = penta 7 = hepta 9 = nona 2 = di 4 = tetra 6 = hexa 8 = octa 10 = deca Steps The first nonmetal only gets a numeric prefix when there is more than one . No prefix if there is only one. The second element always gets a numeric prefix and always has a suffix of – ide. 24

25. Naming Binary Molecular Compounds As with binary ionic compounds, the ending of the name of the second element in the compound is modified by adding the suffix – ide . 25

26. Carbon dioxide CO Carbon monoxide N 2 O 4 Dinitrogen tetroxide H 2 O Dihydrogen monoxide CCl 4 Carbon tetrachloride Name the first element. Since there is only one, no prefix is needed. The second element always gets a prefix and a suffix of –ide . Name the first element. Since there are two present, the prefix “di” is needed. The second element always gets a prefix and a suffix of –ide. 26

27. Silicon dioxide ( SiO 2 ) - Silicon and oxygen are both nonmetals. - The lack of a prefix on silicon means that there is only ONE silicon. - The prefix “di” in front of oxide means that there are TWO oxygens . Diphosphorous pentachloride (P 2 Cl 5 ) - Phosphorous and chloride are both nonmetals. - The prefix “di” means that there are TWO phosphorouses (Is that a word?) - The prefix “penta” before chlorine means that there are five chlorines. 27

28. Nitrogen Monoxide (NO) Nitrogen and oxygen are both nonmetals. The lack of a prefix on nitrogen means only ONE nitrogen. The prefix “mono” on oxygen indicates ONE oxygen. 28

29. 29

30. Ternary Ionic Compounds 30 These Compounds Contain At Least One Polyatomic Ion. What is a polyatomic ion? It is an ion – that means it has a charge. It is polyatomic – that means it is made of more than one atom.

31. Examples 31 CO 3 2- carbonate This ion is composed of one carbon and three oxygen and the entire group has a charge of -2. Polyatomic ion – Group of atoms that act as a unit and carry a charge.

32. How Do You Recognize Ternary Ionic Compounds? Composed of two ions in which at least one is a polyatomic ion. There is only one positive polyatomic ion (NH 4 +1 ) Three possible types of Ternary Ionic Compounds: Ammonium + negative ion (nonmetal) Metal (positive ion) + negative polyatomic ion Ammonium + negative polyatomic ion 32

33. Naming Compounds with Polyatomic Ions as Cation NH 4 Cl is ammonium (the name of the ion from chart) + chlor (root name of the second element) + ide suffix = ammonium chloride. 33

34. Naming Compounds with Polyatomic Ions as Anions Name the first ion. Name the second ion. examples: 34 Na 2 CO 3 When you look at this compound you should recognize that this is NOT binary. There are THREE elements present. When you see this, immediately look for a polyatomic ion. Carbonate is present here. Name the first ion . Name the second ion. Sodium carbonate Notice that you do NOT change the suffix – just name the polyatomic ion .

35. Fe(OH) 3 Iron (III) hydroxide 35 Name the first ion. The Roman Numeral comes from the charge of the ion. How do you find the charge of the iron? All compounds are neutral. C harge of OH (-1) Since there are 3 OH groups, each with a -1 charge, the charge of the iron must be +3 for the compound to be neutral Name the polyatomic ion.

36. THANK YOU 36