1. Review of Atomic Model

2. Elements are pure substances containing one type of atom – found on the Periodic Table. The atom is the smallest part that retains all the properties of that element. protons (p + )neutrons (n o )electrons (e - ) Charge Mass Location +1.6 x 10 -19 C0-1.6 x 10 -19 C 1.67 x 10 -24 g 9.11 x 10 -28 g Nucleus Orbit clouds

3. Octet rule: atoms react to acquire a full outer shell: Give away an e - to another atom. Take an e - from another atom. Share an e - with another atom. Ionic bond Covalent bond An ION is an atom that has lost or gained an electron. H : neutral atom H + : positive cation H - : negative anion

4. +1 +2 -3-2+3 +4/-4 Remember: The number of the column is equal to the valence electron number. Know that and you figure out the number of electrons lost or gained – the ionic charge

5. Ionic NaCl A compound has different characteristic properties than the atoms which form it. Covalent HCl

6. Ionic Compounds Contain a METAL and a NON-METAL atom. Formed by TRANSFERING valence electrons to fill outer shell – octet rule.  A formula unit is the smallest unit of an ionic compound. Metal + Non-metal = ionic bonding

7. Writing Rule 1: Write the symbol of the metallic element first. Be Cl Rule 2: Place the combining capacity of one element as a subscript of the other element. Beryllium combines with Chlorine +- 1 2

8. Rule 3: Leave subscripts with a value of 1 out. Be Cl 21 Two Naming rules: 1.Write the full name of the metal ion first. 2.Name the non-metal ion dropping the last part of the name and adding the suffix “ide”. berylliumchloride

9. Rule 4: Reduce the subscripts if possible. Mg S Magnesium combines with Sulfur Mg S +- 2 2 magnesiumsulphide

10. Transition metals

11. Transition metals can give away different numbers of electrons. To avoid confusion: Brackets are used to show how many electrons the Transition metal is giving away.

12. Iron (III) chloride Iron (II) chloride Fe Cl +- 1 2 FeCl 2 Fe Cl +- 1 3 FeCl 3

13. Write the name of the ionic compound: PbO + - 1 2 lead oxide(IV) +4-2 Remember: Always look at the anion to see if it has been reduced. If it has, so has the metal.

14. Polyatomic Ions (poly = many) Groups of covalently bonded atoms that act as ions in ionic bonding. Polyatomic ions function as one unit with one charge – lose or gain electrons. NEVER change the subscripts of polyatomic ions. Al(C 2 H 3 O 2 ) 3

15. Write the name of the ionic compound: Al(C 2 H 3 O 2 ) Al C 2 H 3 O 2 +- 1 3 aluminum acetate

16. nickel (II) nitrate MgSO 4 potassium permanganate Fe(OH) 3 calcium acetate Ag 2 CrO 4 lead (II) carbonate Sn(SO 4 ) 2 sodium hydrogen phosphate NH 4 NO 2 1.Ni(NO 3 ) 2 2.magnesium sulfate 3.KMnO 4 4.iron (III) hydroxide 5.Ca(C 2 H 3 O 2 ) 2 6.silver chromate 7.PbCO 3 8.tin (IV) sulfate 9.Na 2 HPO 4 10.ammonium nitrite

17. Covalent Compound Contain two or more NON-METAL atoms. Formed by SHARING valence electrons to fill outer shell – octet rule.  A molecule is the smallest unit of a covalent compound. Non-metal + Non-metal = covalent bonding

18. PrefixNumber of Atoms mono1 di2 tri3 tetra4 penta5 hexa6 hepta7 octa8 nona9 deca10

19. Step 1: first non-metal is named with a prefix to show the number of atoms. We do not use “mono” for the first non-metal. nitrogen oxide N O Step 2: second non-metal is named with a prefix AND with the “ide” ending. di 24 tetra dinitrogen tetroxide Prefix Number of Atoms mono1 di2 tri3 tetra4 penta5 hexa6

20. Writing formulas Step 1: Write the symbol of each element. Step 2: Use a subscript to show the number of each type of atom given by the prefix. Do not reduce covalent formulas. phosphorus oxide P O di 2 5 penta Prefix Number of Atoms mono1 di2 tri3 tetra4 penta5 hexa6

21. Does it have a metal? NO (covalent) YES (ionic) Is it a transition? NO charges NO criss-cross Use prefixs Ends in “ide” Find charges Reverse Criss-cross Use Brackets Ends in “ide” Find charges Criss-cross Ends in “ide” MgCl 2 magnesium chloride CuCl 2 copper (II) chloride OCl 2 oxygen dichloride NO YES Polyatomic Find charges Reverse Criss-cross Don’t change ending Fe(NO 3 ) 2 iron (II) nitrate

22. Many reactions are similar Chemists have classified 5 types of reactions BIG PICTURE IDEA: If you know the reactants - you can guess the type of reaction AND predict the products

23. Synthesis A + B  C DecompositionC  A + B Single replacementA + BC  B + AC Double replacement AC + BD  AD + BC Carbon Combustion C x H y + O 2  CO 2 + H 2 O

24. Diatomic Elements: Elements that are most commonly found in a covalent bond with itself. I Have No Bright Or Clever Friends I 2 H 2 N 2 Br 2 O 2 Cl 2 F 2

25. Explain the difference between isotope and radioisotope Explain average atomic mass using isotopes and their relative abundance Additional KEY Terms Radioactive decayHalf-life

26. The atomic number (Z) is the number of protons in the nucleus of an atom - identifies an element. The atomic mass (A) is the number of protons plus the number of neutrons.

27. Isotopes: Atoms with the but a different number of neutrons. same number of protons Deuterium Atomic Mass = 2 Atomic Number = 1 Hydrogen Atomic Mass = 1 Atomic Number = 1 Atomic mass is actually an average of isotopes of an element based on relative abundance in nature

28. Mass spectrometer determines the mass of individual atoms or isotopes. Sends atoms through a magnetic field which bends their paths. The heavier the atom – the less it bends

29. Potassium isotopes: 1. 19 protons and 20 neutrons - mass number of 39 (potassium-39 39 K) 2. 19 protons and 21 neutrons - mass number of 40 (potassium-40 40 K) 3. 19 protons and 22 neutrons - mass number of 41 (potassium-41 41 K)

30. Magnesium exists as three isotopes in the world: 78.99% is 24 Mg (23.985 μ) 10.00% is 25 Mg (24.986 μ) 11.01% is 26 Mg (25.982 μ) (0.7899)(23.985 μ) = 18.95 μ (0.1000)(24.986 μ) = 2.499 μ (0.1101)(25.982 μ) = 2.861 μ = 24.31 μ + Calculate the average atomic mass of magnesium:

31. helium 5 He 6 He The nucleus of some isotopes are unstable and break apart over time - radioactivity.

32. Radioisotopes - unstable nuclei releasing energy and/or particles. Release of energy is called radioactive decay. Half-life - amount of time it takes for half the radioisotope to be converted into another particle. Atoms may be converted into another isotope or a completely different element

33. Many different types of decay exist: alpha decay, beta decay, gamma decay

34. CAN YOU / HAVE YOU? Explain the difference between isotope and radioisotope Explain average atomic mass using isotopes and their relative abundance Additional KEY Terms Radioactive decayHalf-life