1. CHEMISTRY 161 Chapter 2 Compounds and Chemical Reactions

2. 1. Structure of an Atom subatomic particles electrons (‘cloud’) protons (nucleus) neutrons (nucleus) m(n) / m(e) ≈ 2000m(n) > m(p)

3. 2. Atomic & Mass Number atomic number (number of protons) (number of electrons) mass number (number of protons plus neutrons)

4. Compounds & Chemical Reactions 1. Compounds 2. The Chemical Formula 3. The Chemical Equation 4. Energy in Chemical Reactions 5. The Name of Chemicals

5. 1. Compounds molecular compoundsionic compounds EXP1

6. Molecular Compounds 1. consist of electrically neutral particles called molecules 2. each molecule consists of atoms 3. atoms are connected via electrons 4. connections are called bonds (‘springs’) EXP2

7. Molecular Compounds Group Period IVA VA VIA VIIA Noble Gas 2 CH 4 NH 3 H 2 O HF Ne 3 SiH 4 PH 3 H 2 S HCl Ar 4 GeH 4 AsH 3 H 2 Se HBr Kr 5 SbH 3 H 2 Te HI Xe lots of molecules contain hydrogen EXP3

8. H 2, He Jupiter PH 3 CH 4 EXP4

9. H 2, He Saturn NH 3 /PH 3 CH 4 H 2 O (s)

10. atom (neutral) add electron(s) (reduction) anion(Cl - ) (negative charge) take electron(s) (oxidation) cation(Na + ) (positive charge) Ionic Compounds I 1. consist of charged particles 2. charged particles are called ions 3. ions are formed by electron transfers from atoms

11. Ionic Compounds II 4. ionic compounds are held together by electrostatic forces metal non-metal NaClMgO EXP5

12. 2. The Chemical Formula collection of chemical symbols used to describe the composition of elements and compounds EXP6

13. F2F2

14. O2O2

15. S8S8

16. N2N2

17. P4P4

18. H2H2

19. 2. The Chemical Formula collection of chemical symbols used to describe the composition of elements and compounds NaCl H2OH2O Fe 2 O 3 CaSO 4  2 H 2 O

20. Compounds & Chemical Reactions 1. Compounds 2. The Chemical Formula 3. The Chemical Equation 4. Energy in Chemical Reactions 5. The Name of Chemicals

21. 3. The Chemical Equation chemical equation describes what happens in a chemical reaction chemical reaction is combination of elements and/or compounds H 2 + O 2 H 2 O balancing & mass conservation 22 

22. 3. The Chemical Equation 2 H 2 + O 2  2 H 2 O s = solid l = liquid g = gas aq = aqueous solution 2 H 2 (g) + O 2 (g)  2 H 2 O (l)

23. 1.phosphor with oxygen 2. sulfur with oxygen Examples 3. methane with oxygen EXP7

24. Compounds & Chemical Reactions 1. Compounds 2. The Chemical Formula 3. The Chemical Equation 4. Energy in Chemical Reactions 5. The Name of Chemicals

25. 4. Energy in Chemical Reactions a chemical reaction either absorbs or releases energy (heat or light) releasing energy (heat) exothermic absorb energy (heat) endothermic EXP1/2

26. CONSERVATION OF ENERGY KINETIC ENERGY POTENTIAL ENERGY energy of an object due to its motion E kin = ½  m  v 2 energy of an object due to its position E pot = m  g  h E total = E pot + E kin = constant chemical energy is a form of potential energy EXP3

27. Compounds & Chemical Reactions 1. Compounds 2. The Chemical Formula 3. The Chemical Equation 4. Energy in Chemical Reactions 5. The Name of Chemicals

28. Organic Compounds compounds containing mostly hydrogen and carbon minor amount other elements (N, O, S, P…) hydrocarbons HC alkanesC n H 2n+2

29. CO 2 COH2OH2O H 2 COC 4 H 10 Organic Compounds? C 4 H 10 combustion EXP4

30. Titan – Saturn’s Largest Moon

31. Cassini-Huygens Mission

33. Inorganic Compounds binary compounds compounds consisting of ONLY TWO different elements NaClCO 2 CaSO 4 nomenclature naming compounds nomen (Latin) = name

34. symbol stem first element second element O ox- oxygen oxide S sulf- sulfur sulfide N nitr- nitrogen nitride P phosph- phosphorus phosphide F fluor- fluorine fluoride Cl chlor- chlorine chloride Br brom- bromine bromide I iod- iodine iodide part one (metal) part two English name of element stem + ide NaClMgOBeS Metal (Main Group) + Non-Metal

35. ionic compounds (metal + non-metal) stem + ide Nomenclature Inorganic Compounds main group metal metal +

36. Greek Prefixes mono- = 1 (often omitted) hexa- = 6 di- = 2 hepta- = 7 tri- = 3 octa- = 8 tetra- = 4 nona- = 9 penta- = 5 deca- = 10 PF 3 PF 5 COCO 2 HCl NONO 2 N2O5N2O5 Molecular Compounds

37. ionic compounds (metal + non-metal) stem + ide Nomenclature Inorganic Compounds main group metal element + molecular compounds prefix + element + prefix + stem + ide

38. ionic compounds (metal + non-metal) stem + ide Nomenclature Inorganic Compounds main group metal trans. group metal element + molecular compounds prefix + element + prefix + stem + ide

39. ionic compounds cations & anions M n+ E m- metals transition metals nonmetals compounds must be electrically neutral charge state of ions

40. -/+ 3/5 -20 +1+2+3 -/+ 2/4 K2SK2S CaCl 2 main group metals – always start with cation

41. NiCl 2 CuOCuCl transition metals – always start with anions include oxidation state in name – no prefixes Mn 2 O 3 B2O3B2O3

42. ionic compounds (metal + non-metal) stem + ide Nomenclature Inorganic Compounds main group metal trans. group metal element + molecular compounds prefix + element + prefix + stem + ide metal + oxstate +

43. molecular compounds ionic compounds polyatomic ionic compounds ammonium chloridesodium dichromatemagnesium carbonate rubidium sulfatecalcium phosphate

44. molecular & ionic compounds properties melting point molecular compounds – weak interactions (gases, liquids) – low melting point ionic compounds – strong interactions (solids) – high melting point electrical conductivity molecular – do not conduct electricity in solid or liquid state ionic – do not conduct electricity in solid state ionic – conduct electricity in liquid and aqueous state

45. Compounds & Chemical Reactions 1. Compounds 2. The Chemical Formula 3. The Chemical Equation 4. Energy in Chemical Reactions 5. The Name of Chemicals