1. Review for Test 2

2. Atomic Theories Dalton proposed that all matter is made of atoms. Dalton proposed that all matter is made of atoms. Thomson discovered the existence of electrons. Thomson discovered the existence of electrons. Rutherford proposed that the atom has a dense nucleus surrounded by electrons. Rutherford proposed that the atom has a dense nucleus surrounded by electrons. Millikan discovered the charge and mass of electrons. Millikan discovered the charge and mass of electrons. Bohr discovered that the electrons were positioned around the nucleus in well-defined energy levels. Bohr discovered that the electrons were positioned around the nucleus in well-defined energy levels.

3. http://www.chem.uncc.edu/faculty/murphy/1251/slides/C12/sld003.htm

4. Subatomic particle chargelocationmass Other feature proton+Nucleus 1 amu Defines the element -atomic no. neutron0Nucleus 1 amu Change no. to form isotopes electron-Electroncloud ~0~0~0~0 atom’s volume -dictates reactivity

5. Molecular Compounds covalent bond covalent bond Shared electrons Shared electrons nonmetals nonmetals Use prefixes Use prefixes Example: CCl 4 Example: CCl 4 carbon tetrachloride Ionic Compounds ionic bond ionic bond Transferred electrons Metal with nonmetal Balance charges Example: CaCl 2 Calcium chloride

6. Naming molecular compounds Use prefixes 1mono- Use prefixes 1mono- 2di- 3tri- 4tetra- 5penta- 6hexa- 7hepta- 8octa- 9nona- 10deca-

7. Examples P 4 O 10 is tetraphosphorus decoxide P 4 O 10 is tetraphosphorus decoxide N 2 O 3 is dinitrogen trioxide N 2 O 3 is dinitrogen trioxide As 2 O 5 is diarsenic pentoxide As 2 O 5 is diarsenic pentoxide OF 2 is oxygen difluoride OF 2 is oxygen difluoride

8. Write the formulas- balance charges; put the cation first K + and N 3- K3NK3NK3NK3N Ca 2+ and N 3- Ca 3 N 2 Ba 2+ and NO 3 - Ba(NO 3 ) 2 Criss-cross rule of thumb

9. Naming acids anion acid nameexample -ide Hydro- icHCl hydrochloric acid -ite -ousHNO 2 nitrous acid -ate -icHNO 3 nitric acid

10. Types of reactions Decomposition: AB  A + B Synthesis (or “combination”): A + B  AB Single Replacement (or “displacement”): A + BC  B + AC A + BC  B + AC Double Replacement (or “displacement”): AB + CD  AD + CB AB + CD  AD + CB Combustion: CH 4 + 2O 2  CO 2 + 2H 2 O

11. Avogadro’s number 1 mole = 6.02 x 10 23 particles 1 mole = 6.02 x 10 23 particles Molar mass Molar mass One mole of any atom is the atomic mass of that atom, expressed in grams. One mole of any atom is the atomic mass of that atom, expressed in grams.

12. Percent Composition Determine the mass percentage of each element in the compound. Determine the mass percentage of each element in the compound. Mass of element x 100% mass of compound mass of compound What is the percent composition of Fe 2 O 3 ? 2 Fe 2 x 55.8 = 111.6 3 O 3 x 16.0 = 48.0 Formula mass 159.6 %Fe = 111.6/159.6 = 70.0% % O = 48.0/159.6 = 30.0%

13. Determining empirical formula Find the empirical formula of a compound that contains 53.7% iron and 46.3% sulfur. Find the empirical formula of a compound that contains 53.7% iron and 46.3% sulfur. % composition  mass of 100 g sample  moles  mole ratio % composition  mass of 100 g sample  moles  mole ratio 53.7g x 1 mol/55.8g =.962 mol Fe 53.7g x 1 mol/55.8g =.962 mol Fe 46.3g x 1 mol/32.1g = 1.44 mol S 46.3g x 1 mol/32.1g = 1.44 mol S.962/.962 = 1, 1.44/.962 = 1.5.962/.962 = 1, 1.44/.962 = 1.5 1:1.5 ratio x 2 = 2:3 ratio 1:1.5 ratio x 2 = 2:3 ratio Fe 2 S 3 Fe 2 S 3

14. 1. What is the mass in grams of 3.50 moles of copper atoms? 3.50 moles x 63.546g = 222 g Cu 1 mole 1 mole 2. How many moles are in 6.195 g of phosphorus? 6.195g x 1 mole = 0.2000 mole 30.97 g 30.97 g

15. How many moles is 1.20 x 10 23 atoms of Zn? (1.20 x 10 23 atoms) x =.199 moles What is the mass (in grams) of.199 mol of zinc?.199 moles x = 13.0 g

16. How many molecules are in 35.2g of water? 35.2g x 1 mol = 1.96 mol 18.0g 18.0g 1.96 mol x 6.02 x 10 23 = 1.18 x 10 24 molecules 1 mol 1 mol

17. How many atoms are in 0.750 grams Zn? 0.750 g x x = 0.0690 x 10 23 atoms = 6.90 x 10 21 atoms

18. How many protons, electrons, and neutrons are in the following elements? CaHgCo Na + 20 p, 20 e, 20 n 80 p, 80 e, 121 n 27 p, 27 e, 32 n 11 p, 10 e, 12 n

19. Ionic or covalent? NaBr CH 4 Fe 2 O 3 CO 2 CaO NH 4 Cl SiCl 4 Name ionic covalent ionic covalent ionic covalent Sodium bromide Carbon tetrahydride Iron oxide Carbon dioxide Calcium oxide Ammonium chloride Silicon tetrachloride

20. Give the formula Sodium nitrate Nickel sulfate Ammonium chloride Calcium phosphate Copper (II) bromide Magnesium oxide Hydrogen nitrite Aluminum carbonate Lithium hydroxide Iron (III) chlorite NaNO 3 NiSO 4 NH 4 Cl Ca 3 (PO 4 ) 2 CuBr 2 MgO HNO 2 Al 2 (CO 3 ) 3 LiOH Fe(ClO 2 ) 3

21. Dihydrogen monoxide Carbon tetrachloride Sulfur dioxide Triphosphorus hexafluoride Pentanitrogen heptasulfide H2OH2O CCl 4 SO 2 P 3 F 6 N 5 S 7

22. Calcium bromide Chromium (III) acetate Barium sulfate Copper (I) sulfide Sulfur hexafluoride Cr 2 (C 2 O 4 ) 3 Hg(CN) 2 Cu(ClO 4 ) 2 ZnC 4 H 4 O 6 BaSO 4 Cr(C 2 H 3 O 2 ) 3 CaBr 2 Cu 2 S SF 6 Chromium (III) oxalate Mercury (II) cyanide Copper (II) perchlorate Zinc tartrate

23. Try these acids H 2 SO 4 H 2 SO 4 HBr HBr H 3 PO 4 H 3 PO 4 H 2 SO 3 H 2 SO 3 H 2 CO 3 H 2 CO 3 HNO 3 HNO 3 sulfuric acid hydrobromic acid phosphoric acid sulfurous acid carbonic acid nitric acid

24. Balance and classify Al + Cl 2  AlCl 3 Al + Cl 2  AlCl 3 2Al + 3Cl 2  2AlCl 3 Zn + HCl  ZnCl 2 + H 2 Zn + HCl  ZnCl 2 + H 2 Zn + 2HCl  ZnCl 2 + H 2 Zn + 2HCl  ZnCl 2 + H 2 Mg(ClO 3 ) 2  MgCl 2 + O 2 Mg(ClO 3 ) 2  MgCl 2 + O 2 Mg(ClO 3 ) 2  MgCl 2 + 3O 2 C 4 H 8 + O 2  CO 2 + H 2 O C 4 H 8 + O 2  CO 2 + H 2 O C 4 H 8 + 6O 2  4CO 2 + 4H 2 O

25. Complete and balance the following double displacement reaction. 2Na 3 (PO 4 ) + 3Ca(NO 3 ) 2  Ca 3 (PO 4 ) 2 + 6NaNO 3

26. 2 Complete and balance the reaction. Na + Cl 2  Na + Cl 2  2NaCl

27. Name the 7 diatomic elements H2H2H2H2 O2O2O2O2 N2N2N2N2 Cl 2 Br 2 I2I2I2I2 F2F2F2F2

28. How many moles are in 5.6g of NaCl? 5.6 g x 1 mol =.0957 mol 58.5g 58.5g How many grams are in 5.6 moles of NaCl? 5.6 mol x 58.5g = 327.6 g 1 mol 1 mol

29. How many molecules are in 3.5 mol of CaCl 2 ? 3.5 mol x 6.02 x 10 23 molecules = 1 mol 1 mol 2.11 x 10 24 molecules 2.11 x 10 24 molecules How many moles are in 5.5 x 10 22 atoms of Fe? 5.5 x 10 22 atoms x 1 mole = 6.02 x 10 23 molecules 6.02 x 10 23 molecules 0.0914 mol 0.0914 mol

30. How many molecules are in 3.5g of Ca(NO 3 ) 2 ? 3.5g x 1 mol =.0213 mol 164.1g 164.1g.0213 mol x 6.02 x 10 23 molecules = 1 mol 1 mol 1.28 x 10 22 molecules 1.28 x 10 22 molecules