1. Chemical Symbols, Formulas & Equations

2. Chemical Symbols A symbol represents one element (1-3 letters) Symbol Writing Rules 1 st letter is always capitalized 2 nd & 3 rd letters (if any) are always lower case Symbols O Oxygen Sn Tin Uut Ununtrium Co Cobalt element #27 bluish metal CO Carbon monoxide Molecule: ( 1 carbon, 1 oxygen) colorless, odorless, tasteless, deadly gas Co v CO

3. IUPAC Naming New Elements New elements are being synthesized (made) in the lab Names for the element has to wait until the IUPAC naming committee meets A temporary name based on the atomic number IN LATIN is given to the new element Time to learn some Latin Rules for naming elements 1. Break up the atomic number into digits (#118 becomes 1, 1, 8) 2. Replace the digits with the Latin number (1, 1, 8 becomes un un oct 3. Put the Latin numbers together and add “–ium” ending – ununoctium 4. The symbol is the first letter of each of the Latin numbers (follow the rules) ununoctium - Uuo 1 – un 2 – bi 3 – tri 4 – quad 5 – pent 6 – hex 7 – sept0-nil 8 – oct 9 – enn

4. IUPAC Samples Atomic NumberSymbol 113 Uut Name ununtrium 234 Btq bitriquadium 506 Pnh pentnilhexium

5. Chemical Formulas Chemical “shorthand” to describe a compound Gives the symbol & number of atoms of each element Rules for Formulas 1. every Capital letter indicates another element 2. a lowered number (called a subscript) after an element tells you how many atoms of that element are in the compound/molecule (no subscript means 1) 3. A number in front of a FORMULA tells you how many units or molecules of that substance there are (this is called the formula coefficient)

6. Examples (Formula Rules 1 & 2) CompoundFormula# Atoms of Each Element Carbon DioxideCO 2 1 -Carbon2- Oxygens SugarC 6 H 12 O 6 6-Carbons12 - Hydrogens6-Oxygens Copper SulfateCuSO 4 1-Copper1-Sulfur4-Oxygens Baking SodaNaHCO 3 1-Sodium1-Hydrogen1-Carbon3-Oxygens

7. Polyatomic Ions (parts in parentheses) Some combinations of elements bond together and act like an element – they usually stay together Examples: Phosphate PO 4 Hydroxide OH Ammonium NH 4 Acetate C 2 H 3 O 2 Nitrate NO 3 Because there is more than one element bonded together, if more than one polyatomic ion is needed you Wrap parentheses around the ion in the formula Put the subscript outside the parentheses

8. Counting Elements with () Since the polyatomic ion acts like an element, its subscript multiplies the number of ions needed Ex. ClO 3 is a poly atomic ion called chlorate so… Mg(ClO 3 ) 2 means we have 1 magnesium and 2 chlorates But each chlorate is 1-chlorine and 3-oxygens Therefore the subscript outside the () multiplies the each of the number of elements inside the parentheses for the total (ClO 3 ) 2 ends up with 2-chlorines (2 *1) and 6- oxygens (2*3)

9. Counting with Polyatomic Ions Samples FormulaElement Count Ca 3 (PO 4 ) 2 Al(C 2 H 3 O 2 ) 3 3-Calcium 2-Phosphorous (2*1) 8-Oxygen (2*4) 1-Aluminum 6-Carbon (3*2) 9-Hydrogen (3*3) 6-Oxygen (3*2) Al

10. Review Practice CompoundContents HgBr 2 Be(NO 3 ) 2 Al(C 2 H 3 O 2 ) 3 1-Mercury 2-Bromine 1-Beryllium 2-Nitrogen (1*2) 6-Oxygen (3*2) 1-Aluminum 6 Carbon (2*3) 9-Hydrogen (3*3) 6-Oxygen (2*3)

11. Example (Formula Rule #3) C 2 H 6 O + 3O 2  3H 2 O + 2CO 2 1- C 2 H 6 O molecule is needed (no number means 1) 3- O 2 molecules are needed 3- H 2 O molecules are needed 2- CO 2 molecules are needed 2-Carbons 6-Hydrogens 1-Oxygen 6-Oxygens 6-Hydrogens 3-Oxygens 2 Carbons 4-Oxygens

12. Coefficient Samples FormulaContents 4 H 2 O 2 MgCl 2 3 C 6 H 12 O 6 4*2 = 8 Hydrogen 4*1 = 4 Oxygen 2*1 = 2 Magnesium 2*2 = 4 Chlorine 3*6 = 18 Carbon 3*12 = 36 Hydrogen 3*6 = 18 Oxygen Do # 18, 19, 20 on back page

13. Review Video

14. Putting it all together Since a coefficient multiplies the number of compounds then The coefficient will also multiply the number of polyatomic ions Rule: The coefficient AND a subscript outside the parentheses BOTH multiply the elements inside the parentheses. Example 3 Ca 3 (PO 4 ) 2 9-Calcium (3*3) 6-Phosphorus (3*1*2) 24-Oxygen *(3*4*2)

15. Other Examples CompoundCount 3 (NH 4 ) 2 SO 4 4 Cu(NO 3 ) 2 6-Nitrogen (3*1*2) 24-Hydrogen (3*4*2) 3-Sulfur (3*1) 12-Oxygen (3*4) 4-Copper (4*1) 8-Nitrogen (4*1*2) 24-Oxygen (4*3*2)

16. Conservation of Mass Matter cannot be created or destroyed (actually the law states that the total amount of matter + energy in a closed system remains constant but that is a little lofty for what we will be doing) For Us: In a reaction the total number of elements we start the reaction with must equal the total number of elements we end with. Example H 2 + O 2  H 2 O Since the totals on each side of the  are not equal we need to use coefficients to “balance” the equation

17. Balancing a Chemical Equation Samples S + O 2  SO 2 1- sulfur 2-oxygen 1-sulfur 2-oxygen 1-sodium 2-oxygen 2-sodium 1-oxygen   Na + O 2  Na 2 O x2 1-sodium 2-oxygen 4-sodium 2-oxygen  x4 4-sodium 2-oxygen 4-sodium 2-oxygen  4 Na + O 2  2Na 2 O Na + O 2  2 Na 2 O H 2 + Cl 2  HCl 2- hydrogen 2-chlorine 1-hydrogen 1-chlorine  H 2 + Cl 2  2HCl 2-silver 1-oxygen 1-silver 2-oxygen  x2 4-silver 2-oxygen 1-silver 2-oxygen  2 Ag 2 O  Ag + O 2 x2 2- hydrogen 2-chlorine 2-hydrogen 2-chlorine  Ag 2 O  Ag + O 2 2 Ag 2 O  4Ag + O 2 x4

18. Balancing a Chemical Equation EquationProcedure H 2 + O 2  H 2 O Count the atoms on each side of the equation (  ) 2-hydrogen 2-oxygen 2-hydrogen 1-oxygen need to multiply the oxygen on the right by 2 2-hydrogen 2-oxygen 4-hydrogen 2-oxygen   4-hydrogen 2-oxygen 4-hydrogen 2-oxygen  x2 2H 2 + O 2  2H 2 O H 2 + O 2  2H 2 O Select one of the elements that are out of balance and use a coefficient to multiply its compound & recount Repeat this process until all elements are balanced (numbers of an element are the same on each side) Change ONLY the COEFFICIENTS, NEVER the SUBSCRIPTS!!

19. 1- carbon 4-hydrogen 2-oxygen 1- carbon 2-hydrogen 3-oxygen Balancing a Chemical Equation Samples CO + O 2  CO 2 1- carbon 3-oxygen (1/2) 1-carbon 2-oxygen 2-nitrogen 2-hydrogen 1-nitrogen 3-hydrogen   N 2 + H 2  NH 3 x2 2-nitrogen 6-hydrogen 2-nitrogen 6-hydrogen  2 CO + O 2  2CO 2 N 2 + 3H 2  2NH 3 CH 4 + O 2  CO 2 + H 2 O 1- carbon 4-hydrogen 2-oxygen  CH 4 + O 2  CO 2 + 2H 2 O  x2 CH 4 + 2O 2  CO 2 + 2H 2 O x2 x2 just the CO x3 2-carbon 4-oxygen (1/2) 2-carbon 4-oxygen  1- carbon 4-hydrogen 4-oxygen 1- carbon 4-hydrogen 4-oxygen  1- carbon 4-hydrogen 4-oxygen

20. 2- hydrogen 2-nitrogen 1-oxygen Balancing a Chemical Equation Samples H 2 + NO  H 2 O + N 2 2- hydrogen 1-nitrogen 1-oxygen  H 2 + 2NO  H 2 O + N 2  x2  H 2 + 2NO  2H 2 O + N 2 x2  2- hydrogen 2-nitrogen 2-oxygen 2- hydrogen 2-nitrogen 1-oxygen 2- hydrogen 2-nitrogen 2-oxygen 4- hydrogen 2-nitrogen 2-oxygen 2H 2 + 2NO  2H 2 O + N 2 2- hydrogen 2-nitrogen 2-oxygen 4- hydrogen 2-nitrogen 2-oxygen