Chemical Names and Formulas

1. Chemical Names and Formulas EQ: What is the systematic way of naming chemical compounds?

2. Writing Formulas for Binary Ionic Compounds • Write the symbol for the cation, then write the symbol for the anion. Add whatever subscripts are needed to balance the charges. • For EXAMPLE: Cation: Fe3+ Anion: O2- Formula: Fe3+ O2- Fe2O3

3. Naming Binary Ionic Compounds • A binary compound is composed of two elements and can be either ionic or molecular. • If you know the formula for a binary ionic compound, you can write its name. • To name any binary ionic compound, place the cation name first, followed by the anion name (and REMEMBER to add the –ide ending)

4. Practice Naming Binary Ionic Compounds • NaBr • KI • LiCl • CaO • MgCl2 sodium bromide potassium iodide lithium chloride calcium oxide magnesium chloride

5. What about transition metals? • Remember Fe2O3? • The charges of the cations of many transition metal ions must be determined from the number of electrons lost. • For example, iron forms two common cations, Fe2+ (two electrons are lost) and Fe3+ (three electrons are lost). • When naming the cation of a transition metal, a roman numeral (which corresponds to the oxidation number) is placed after the element. • Fe2O3 is named Iron(III) oxide, because the iron in this compound is Fe3+

6. Let’s try it? • Table 9.2 on page 255 is very helpful!!! • CuO • PbBr4 • CoCl2 • Tin (II) oxide Copper (II) oxide Lead (IV) bromide Cobalt (II) chloride SnO

7. Polyatomic Ions EQ: What are polyatomic ions and how do we name them?

8. Polyatomic Ions • Polyatomic ions are ions composed of more than one atom. • They behave as a unit and carry a charge. • Table 9.3 page 257 “Common Polyatomic Ions”

9. Naming of Polyatomic Ions The names of polyatomic ions end in –iteor –ate. -ite -ate • Sulfite, SO32- • Nitrite, NO2- • Chlorite, ClO2- • Sulfate, SO42- • Nitrate, NO3- • Chlorate, ClO3-

10. Practice with Polyatomic Ions • Potassium + carbonate • Aluminum + carbonate K2CO3 potassium carbonate Al2(CO3)3 aluminum carbonate

11. Covalent Compounds EQ: How do we name covalent compounds?

12. Dihydrogen Monoxide • What are the dangers associated with dihydrogen monoxide? • Death due to accidental inhalation of DHMO, even in small quantities. • Prolonged exposure to solid DHMO causes severe tissue damage. • Excessive ingestion produces a number of unpleasant though not typically life-threatening side-effects. • DHMO is a major component of acid rain. • Gaseous DHMO can cause severe burns. • Contributes to soil erosion. • Leads to corrosion and oxidation of many metals. • Contamination of electrical systems often causes short-circuits. • Exposure decreases effectiveness of automobile brakes. • Found in biopsies of pre-cancerous tumors and lesions. • Given to vicious dogs involved in recent deadly attacks.

13. Dihydrogen Monoxide • What are some of the uses of dihydrogen monoxide? • in nuclear power plants, • by the U.S. Navy in the propulsion systems of some older vessels, • by elite athletes to improve performance, • in the production of Styrofoam, • in biological and chemical weapons manufacture, • in the development of genetically engineering crops and animals, • as a spray-on fire suppressant and retardant, • in cult rituals, • historically, in Hitler's death camps in Nazi Germany, and in prisons in Turkey, Serbia, Croatia, Libya, Iraq and Iran, • in World War II prison camps in Japan, and in prisons in China, for various forms of torture, • by many terrorist organizations including al Quaeda, • in community swimming pools to maintain chemical balance, • in day care centers, purportedly for sanitary purposes, • in animal research laboratories, and • in pesticide production and distribution.

14. Dihydrogen Monoxide • Do you think we should continue the use of dihydrogen monoxide, or ban it? • What is dihydrogen monoxide? H2O WATER

15. Naming Binary Molecular Compounds • Review: • Binary Ionic Compounds are composed of the ions of two elements, a metal and a nonmetal. • Binary Molecular Compounds are composed of two elements , both nonmetals and are NOT ions. • Think covalent bond!!!

16. Binary Molecular Compounds • Table 9.4 page 269 • A prefix in the name of a binary molecular compound tells how many atoms of an element are present in each molecule of the compound • Remember the suffix or ending is still –ide.

17. Lets practice? Nitrogen trichloride • NCl3 • CO2 • CO • N2H4 • Dinitrogen trioxide • Dichlorineheptoxide Carbon dioxide Carbon monoxide Dinitrogentetrahydride N2O3 Cl2O7

18. Contains Prefixes? Molecular Compound Use prefixes to write formula Yes No Ionic Compound Group A Elements Use periodic table +1,+2,+3… -3, -2, -1 Roman Numerals Give charges for cations. Polyatomic ions Use Polyatomic ion chart Balance Charges Use crisscross method.

19. REVIEW • An –ide ending generally indicates a binary compound. • An –ite or –ate ending means a polyatomic ions that includes oxygen in the formula. • Prefixes in a name generally indicate that the compound is molecular (covalently bonded). • A Roman numeral after the name of a cation shows the ionic charge of the cation (for transition metals… except Ag ,Zn,Cd).