chapter 7- chemical formulas and chemical compounds
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Chapter 7- Chemical Formulas and Chemical Compounds. Ban Dihydrogen Monoxide!. Colorless, odorless, tasteless Kills uncounted thousands of people every year. Most deaths caused by accidental inhalation Prolonged exposure to its solid form causes severe tissue damage. - PowerPoint PPT PresentationTRANSCRIPT
Chapter 7- Chemical Formulas and Chemical
Compounds
Ban Dihydrogen Monoxide! Colorless, odorless, tasteless Kills uncounted thousands of people every year. Most deaths caused by accidental inhalation Prolonged exposure to its solid form causes severe
tissue damage. Symptoms of ingestion can include
excessive sweating and urination, a bloated feeling, nausea, vomiting body electrolyte imbalance.
For those who have become dependent, withdrawal means certain death.
Ban Dihydrogen Monoxide! Also known as hydroxl acid Major component of acid rain Contributes to the "greenhouse effect." May cause severe burns. Contributes to the erosion of our natural landscape. Accelerates corrosion and rusting of many metals. May cause electrical failures and decreased
effectiveness of automobile brakes. Been found in excised tumors of terminal cancer
patients. Is now an ingredient in most foods and beverages
Ban Dihydrogen Monoxide!Based on the evidence presented in the
previous two slides, do you support the banning of dihydrogen monoxide?
Write at least two sentences stating your reasoning.
Please sign the petition!
What is Dihydrogen Monoxide?
Chemical Formulas Indicate the relative number of atoms or
ions of each kind in a chemical compound
C8H18
MgCl2
Ca(OH)2
8 C atoms 18 H atoms
2 OH- ions
2 Cl- ions
1 Ca2+ ion
1 Mg2+ ion
Monatomic Ions Ions formed from a single atomUsually have noble gas configurationsThat’s how we determine its chargeExample:
Li: 1s22s1
Li+: 1s2 or [He]Table on p.221 on monatomic ions
Naming Monatomic CationsUse the element’s name!Yes, it’s that simple!Example:
Cs+ = cesiumAl3+ = aluminum
Naming Monatomic AnionsDrop the ending of the element’s nameAdd the ending –ideExamples:
Cl- = chlorideN3- = nitride
Naming Monatomic IonsK+
S2-
Rb+
O2-
I-
Ba2+
Cu+
potassiumsulfiderubidiumoxide iodidebariumcopper
Binary Ionic CompoundsCompounds composed of two ionsTotal numbers of positive charges and
negative charges must be equalExamples:
NaClKBrCaF2
Writing Binary Ionic CompoundsWrite the symbols for the ions side by
side. Write the cation first.Al3+ O2-
Cross over the charges to use as the subscript for the other ion.
Al3+ O2-
Al2 O3
Writing Binary Ionic CompoundsCheck the subscripts and divide them to
give the smallest whole number ratio of ions.
Al2O3
Write the formula!Al2O3
Writing Binary Ionic CompoundsZinc iodideBarium fluorideLithium oxideCalcium oxideMagnesium bromide
ZnI2
BaF2
Li2OCaOMgBr2
Naming Binary Ionic Compounds
Give name of cation firstThen name the anionAl2O3
Name of cation: aluminumName of anion: oxideName of compound: aluminum oxide
Naming Binary Ionic Compounds
BaI2
ZnF2
K2OMgOCaBr2
Barium iodideZinc fluoridePotassium oxideMagnesium oxideCalcium bromide
Cations With Different ChargesSome elements form two or more cations
with different chargesFe2+ and Fe3+
Iron (II) and Iron (III)Naming compounds
FeO and Fe2O3
Iron (II) oxide and Iron (III) oxide
Name the Following Compounds
CuOCoF3
SnI4
FeS
Copper (II) oxideCobalt (III) fluorideTin (IV) iodide Iron (II) sulfide
Quiz- Name the Following Compounds
1. K2S2. AgBr3. Na2O4. FeCl25. BaS
6. Lithium fluoride7. Silver iodide8. Iron (III) oxide9. Magnesium iodide10. Gold chloride
Polyatomic Ions Ions that contain two or more atomsMost are negatively chargedList of polyatomic ions is on handout
**MEMORIZE THEM!!!**Examples:
CN- cyanideHCO3
- hydrogen carbonate (bicarbonate)NH4
+ ammonium
Polyatomic IonsYou will need to memorize the following:
Ammonium NH4+1
Acetate C2H3O2-1
Hydroxide OH-1
Nitrite NO2-1
Nitrate NO3-1
Bicarbonate HCO3-1
Carbonate CO3-2
Chromate CrO4-2
Sulfate SO4-2
Phosphate PO4-3
OxyanionsPolyatomic ions that contain oxygenName depends on number of oxygen
atoms
Oxyanions (cont.) If two oxyanions-
Most oxygens: -ateLeast oxygens: -ite
ExampleNO3
- : nitrateNO2
- : nitrite
Oxyanions (cont.) If more than two oxyanions
Most oxygens: “Per- …. –ate” “-ate” “-ite” Least oxygens: “Hypo- …. –ite”
Example ClO4
- : perchlorate ClO3
- : chlorate ClO2
- : chlorite ClO- : hypochlorite
Polyatomic Ion Quiz
Sodium hypochloritePotassium sulfateMagnesium peroxideAmmonium chlorideLithium nitratePotassium phosphate
NaClOK2SO4
MgO2
NH4ClLiNO3
K3PO4
Polyatomic Ion Quiz1. Bicarbonate2. Acetate3. Bisulfite4. Permanganate5. Nitrite6. Cyanide7. Hydroxide8. Bisulfate9. Nitrate10. What’s your favorite polyatomic ion?
Binary Molecular CompoundsComposed of molecules (covalently
bonded!)A nonmetal bonded to another nonmetalExamples:
SO3
ICl3CH4
H2O
Prefixes for Naming Binary Molecular Compounds
1 mono- 2 di- 3 tri- 4 tetra- 5 penta- 6 hexa- 7 hepta- 8 octa- 9 nona- 10 deca
Naming Binary Molecular Compounds
Which element goes first? Smaller group number If same group- greater period number Use prefix only if there is more than one atom
Second element Prefix indicating number of atoms + root of the name
of the element + -ide General order of elements in binary compounds:
C, P, N, H, S, I, Br, Cl, O, F
Naming Binary Molecular Compounds
Examples:SO3 – sulfur trioxideBrCl3 – bromine trichloridePBr5 – phosphorus pentabromideN2O5 – dinitrogen pentoxide
Naming Binary Molecular Compounds
N2OCCl4NOCO2
N2O3
P4O10
Dinitrogen monoxideCarbon tetrachlorideNitrogen monoxideCarbon dioxideDinitrogen trioxideTetraphosphorus decoxide
Naming Binary Molecular Compounds- More Practice!
Disulfur dioxideSilicon tetrafluorideSulfur monoxidePhosphorus trioxideBoron trifluorideDiphosphorus pentoxide
S2O2 SiF4
SOPO3
BF3
P2O5
Acids Acid- a type of molecular compound
Two types Binary acids- made up of two elements- hydrogen, and one
of the halogens (F, Cl, Br, I) Oxyacids- contain hydrogen, oxygen, and a third element
Examples Binary acids:
HCl- hydrochloric acid; HF- hydrofluoric acid Oxyacids:
H2SO4: sulfuric acid HNO3: nitric acid
Formula MassThe sum of the atomic masses of all
atoms represented in its formulaUnits = amu (atomic mass units)Example: What is the formula mass of
water?2 H atoms @ 1.01 amu each = 2.02 amu1 O atom @ 16.00 amu each = 16.00 amuTotal mass of water = 16.00 + 2.02 = 18.02
Formula MassFind the formula mass of the following:
KClO3
H2SO4
Mg(NO3)2
C12H22O11
Molar MassThe mass in grams of one mole of a
substance If we have 1 mole of H2O, we have
2 moles of H atoms1 mole of O atoms
Molar Mass (cont.)How many moles of each atom are in the
following?CaCl2NaOHKMnO4
NH4OHMg(NO3)2
Molar Mass (cont.)Once we know the number of moles of
each atom, we can calculate the molar mass.
In H2O:2 moles H x 1.01 g H = 2.02 g H
1 mole H
1 mole O x 16.00 g O = 16.00 g O 1 mole O
Molar Mass (cont.)
Total mass of 1 mole H2O 2.02 g + 16.00 g = 18.02 g/mol
Molar Mass (cont.)Determine the molar mass of the following:
CaCl2NaOHKMnO4
NH4OHMg(NO3)2
Molar Mass as a Conversion Factor
Can use molar mass as a conversion factor to determine number of moles
How many moles of H2O are in 34.32 g?
Molar Mass as a Conversion Factor
How many molecules of NaCl can be found in a sample containing 45.43 g?
Molar Mass as a Conversion Factor
How many carbon atoms are in a 23.43 g sample of CO2?
Fun With Conversions! Ibuprofen, C13H18O2, is the active
ingredient in Advil. Find its molar massIf the tablets in the bottle contain a total of 33
g of ibuprofen, how many moles of ibuprofen are in the bottle?
How many molecules of ibuprofen are in the bottle?
What is the total mass in grams of carbon in 33 g of ibuprofen?