Unit 2Chemistry

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Topic 2-01

GROUP:

versus

PERIOD:

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Naming "Facts" to Know

1. The Chemical Formulas of Individual Elements:The formulas of all chemical elements with the exception of those listed below consists of simply the chemical symbol for that element and the state (solid (s), liquid (l) or gas (g)) of the element.Examples:

iron: Fe(s) mercury: Hg(l) helium: He(g)

Exceptions:Hydrogen, oxygen, nitrogen and All halogens (Group VIIA) exist as diatomic elements; their formulas are then:H2(g) , hydrogen For the diatomicO2(g) , oxygenF2(g) , fluorine elements, remember:Br2(l) , bromine (note that this is a liquid) 7-Up!I2(s) , iodine (note that this is a solid)N2(g) , nitrogenCl2(g) , chlorine

Also:P4(s), phosphorusS8(s), sulfur

2. The following "SI prefixes" used in naming molecular compounds must also be known:1: mono- 6: hexa-2: di- 7: hepta-3: tri- 8: octa-4: tetra- 9: nona-5: penta- 10: deca-

3. The following common molecular formulas with traditional names exist.For test and exam purposes, only the traditional names which are underlined and in bold below need to be known:

ozone: O3(g)water: H2O(l)ammonia: NH3(g)hydrogen peroxide: H2O2(l)sucrose: C12H22O11(s)

methane: CH4(g)methanol: CH3OH(l)ethanol: C2H5OH(l)benzene: C6H6(l)propane: C3H8(g)

4. Some Roman Numerals, needed for the names of the groups in the Periodic Table and other chemical naming, are:

1 = I 6 = VI2 = II 7 = VII3 = III 8 = VIII4 = IV 9 = IX5 = V 10 = X

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Topic 2-02 Naming and Writing Formulas for Binary Molecular Compounds

Molecular compounds: contain nonmetals only.

Remember: The nonmetals are to the right side of the "staircase" in the Periodic Table.

A binary molecular compound contains two different nonmetal elements.

RULES: Naming Molecular CompoundsStep 1: Verify that the formula has nonmetals only. Look to see if a traditional name or a

molecular element is given.

Step 2: The first element in the formula uses its full name from the periodic table. There are no changes to the ending.The second element in the formula switches its ending to "-ide".

Step 3: Use the SI prefixes (from the "Naming Facts" sheet) to indicate the number of each atom in the formula.Additional Notes:- Do not use "mono" in the name of the first element if there is only "1" of the

first element.- When combining a prefix and a name, do not use "oo" or "ao"; just use a single

"o". Example: "tetraoxide" is not used'; use "tetroxide" instead.- "hydrogen" compounds do not use "mono" for the second element.

Example: HCl is "hydrogen chloride", not "hydrogen monochloride".

Sample ProblemName each compound using IUPAC rules, unless a traditional name exists.(a) P2F6

(b) NBr3

(c) NH3

(d) HF

(e) O2F

(f) SO

(g) Br2

(h) S8

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Worksheet 2-02 Writing Chemical Formulas ELEMENTS andMOLECULAR COMPOUNDSGive the correct chemical formulas for:

(1) nitrogen tribromide _____________ (23) ozone _____________(2) phosphorus difluoride _____________ (24) nitrogen monoxide _____________

(3) diphosphorus tetrafluoride _____________ (25) ammonia _____________

(4) magnesium _____________ (26) water _____________

(5) manganese _____________ (27) helium _____________

(6) chlorine _____________ (28) hydrogen _____________

(7) carbon monoxide _____________ (29) mercury _____________

(8) carbon dioxide _____________ (30) sulfur hexabromide _____________

(9) hydrogen peroxide _____________ (31) diselenium heptaiodide _____________

(10) iodine pentachloride _____________ (32) beryllium _____________

(11) iodine _____________ (33) boron _____________

(12) carbon _____________ (34) bromine _____________

(13) phosphorus _____________ (35) potassium _____________

(14) triphosphorus diselenide _____________ (36) silicon tetrabromide _____________

(15) sulfur trioxide _____________ (37) carbon tetrachloride _____________

(16) sulfur dioxide _____________ (38) trinitrogen heptafluoride _____________

(17) nitrogen _____________ (39) sodium _____________

(18) nickel _____________ (40) sulfur _____________

(19) boron trichloride _____________ (41) silver _____________

(20) oxygen _____________ (42) oxygen difluoride _____________

(21) selenium _____________ (44) tungsten _____________

(22) bromine monofluoride _____________ (45) iron _____________

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Worksheet 2-02 Naming Chemicals ELEMENTS andMOLECULAR COMPOUNDSState the correct IUPAC name for the ionic formula given.

(1) CF4 _________________________ (23) Cu _________________________

(2) BCl3 _________________________ (24) Co _________________________

(3) N2O _________________________ (25) F2O _________________________

(4) SO3 _________________________ (26) N2 _________________________

(5) SO _________________________ (27) B2Cl6 _________________________

(6) O2 _________________________ (28) S4I4 _________________________

(7) O3 _________________________ (29) H2 _________________________

(8) F2 _________________________ (30) H2O _________________________

(9) K _________________________ (31) H2O2 _________________________

(10) P4 _________________________ (32) NI3 _________________________

(11) N2O2 _________________________ (33) N2F4 _________________________

(12) Ni _________________________ (34) S2O _________________________

(13) Na _________________________ (35) Al _________________________

(14) S8

_________________________ (36) Zn _________________________

(15) SeS _________________________ (37) Zr _________________________(16) SeI2 _________________________ (38) Mn _________________________

(17) Fe _________________________ (39) Mo _________________________

(18) NH3 _________________________ (40) IF5 _________________________

(19) NF3 _________________________ (41) Cl2S _________________________

(20) Se3I5 _________________________ (42) BrF7 _________________________

(21) Cd _________________________ (43) BrI _________________________

(22) Hg _________________________ (44) Cr _________________________

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Topic 2-03a Binary Ionic Compounds, Part 1: Writing Chemical Formulas

An ionic compound has a cation (+) and an anion (-).

A binary ionic compound has only two different elements present. The first element in the formula is the metal (+); the second element in the formula is the nonmetal (-).

Steps: Writing the Chemical Formula of a Binary Ionic CompoundStep 1: From the given name, write the symbol for the metal cation and its (+) charge. Then write

the symbol of the nonmetal anion and its (-) charge.

Important: Determine the charge on each ion as follows:For main group ions (the "A" groups), the charge depends upon the group number:

Group 1 (IA): +1 Group 5 (VA): -3Group 2 (IIA): +2 Group 6 (VIA): -2Group 3 (IIIA): +3 Group 7 (VIIA): -1Group 4 (IVA): no ions (X)

For transition metal ions (the "B" groups), look for the charge given by a Roman numeral. (This is because most transition metal ions may have more than one possible charge.)The three exceptions to the "Roman numeral" rule:

"cadmium" is Cd2+ "zinc" is Zn2+"silver" is Ag+

For these three transition metals, the charge does not vary, so no Roman numeral is given.

The graphic below may help remember the above:

Step 2: Ask: Are the charges "equal and opposite"?If yes: then write the final answer by putting the two symbols together, metal first, nonmetal second. Do not include the charges in your final chemical formula.If no: then "criss cross" the charges to become subscript numbers (see examples). Make sure that the final ionic formula is in lowest terms.

.

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Sample ProblemWrite the correct chemical formula for:(a) magnesium oxide

(b) aluminum selenide

(c) lead(II) bromide

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(d) cadmium fluoride

(e) manganese(IV) sulfide

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Worksheet 2-03a Writing Chemical Formulas BINARY IONICGive the correct chemical formulas for: COMPOUNDS

(1) sodium bromide _____________ (23) potassium chloride _____________

(2) iron(III) oxide _____________ (24) vanadium(V) nitride _____________

(3) aluminum iodide _____________ (25) aluminum nitride _____________

(4) manganese(II) sulfide _____________ (26) gallium iodide _____________

(5) manganese(IV) sulfide _____________ (27) lead(II) iodide _____________

(6) magnesium sulfide _____________ (28) lead(IV) iodide _____________

(7) cadmium selenide _____________ (29) copper(II) chloride _____________

(8) vanadium(IV) fluoride _____________ (30) cadmium chloride _____________

(9) silver oxide _____________ (31) strontium nitride _____________

(10) rubidium nitride _____________ (32) lithium chloride _____________

(11) aluminum phosphide _____________ (33) titanium(III) oxide _____________

(12) zinc chloride _____________ (34) titanium(IV) oxide _____________

(13) strontium sulfide _____________ (35) silver nitride _____________

(14) cesium oxide _____________ (36) iron(III) sulfide _____________

(15) cobalt(III) chloride _____________ (37) iron(III) phosphide _____________

(16) manganese(IV) selenide ___________ (38) sodium fluoride _____________

(17) lithium oxide _____________ (39) nickel(II) selenide _____________

(18) beryllium bromide _____________ (40) nickel(II) nitride _____________

(19) calcium oxide _____________ (41) nickel(III) nitride _____________

(20) chromium(II) oxide _____________ (42) magnesium chloride _____________

(21) chromium(III) oxide _____________ (43) beryllium oxide _____________

(22) chromium(IV) oxide _____________ (44) barium bromide _____________

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Topic 2-03b Binary Ionic Compounds, Part 2: Naming CompoundsRecall: A binary ionic compound has: a metal cation (+), and

a nonmetal anion (-).

Steps: How to Name a Binary Ionic CompoundStep 1: The metal element name matches the name in the Periodic Table.

For main group (Group "A" elements), this is all that is needed for the metal name. If the metal element is a transition metal (Group "B" element), then a Roman numeral is also used to indicate the charge when more than one charge is possible.

2+

Remember: "cadmium" is always Cd"zinc" is always Zn2+

+

"silver" is always Ag

Step 2: The nonmetal element uses the "-ide" ending.

Important notes: - never use the prefixes "di-, tri-, tetra-" for these binary ionic compounds!- when a transition metal is present , always check the total charge to

ensure that the correct metal cation (+) charge is used.

Sample ProblemWrite the correct chemical names for:(a) MgO

(b) FeO

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(c) CaI2

(d) CuI2

(e) CdI2

(f) Al2S3

(g) TiS2

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Worksheet 2-03b Naming Chemicals BINARY IONIC COMPOUNDSState the correct IUPAC name for the ionic formula given.

(1) CaF2 _________________________ (23) CsI _________________________

(2) CsCl _________________________ (24) CuI _________________________

(3) FeO _________________________ (25) CaI2 _________________________

(4) Fe2O3 _________________________ (26) CuI2 _________________________

(5) Al2O3 _________________________ (27) CdI2 _________________________

(6) MnO _________________________ (28) CrI2 _________________________

(7) MgO _________________________ (29) SnI2 _________________________

(8) MnO2 _________________________ (30) CoI2 _________________________

(9) K3N _________________________ (31) CrI3 _________________________

(10) VS2 _________________________ (32) CoI3 _________________________

(11) V2S5 _________________________ (33) PdF4 _________________________

(12) Ag2O _________________________ (34) NbN _________________________

(13) Ti2Se3 _________________________ (35) Na3N _________________________

(14) ZnBr2 _________________________ (36) NiN _________________________

(15) BaSe _________________________ (37) TiN _________________________

(16) AlF3 _________________________ (38) CaS _________________________

(17) NiO _________________________ (39) CoS _________________________

(18) Ni2O3 _________________________ (40) CdS _________________________

(19) Be3P2 _________________________ (41) CuS _________________________

(20) Ru2Se3 _________________________ (42) Cu2S _________________________

(21) RuSe _________________________ (43) CrS _________________________

(22) GaP _________________________ (44) SrS _________________________

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Worksheet 2-03c

Molecular or Ionic?

For each question, first determine whether it is a molecular compound or an ionic compound.Then complete the question by either naming the chemical or writing its formula.

1 calcium bromide 24 K2S2 carbon tetrabromide 25 O2S

3 zinc chloride 26 LiF

4 diphosphorus dichloride 27 IF

5 lithium nitride 28 BrF

6 magnesium nitride 29 NaBr

7 trisulfur tetranitride 30 MgSe

8 carbon monoxide 31 MnSe

9 iron(III) sulfide 32 SSe

10 iron(II) sulfide 33 MnSe2

11 strontium sulfide 34 SrSe

12 selenium monosulfide 35 CuSe

13 copper(II) oxide 36 Cu2Se

14 copper(I) oxide 37 Na3P

15 tin(IV) oxide 38 N3P

16 tetraphosphorus dioxide 39 NP

17 diphosphorus tetroxide 40 PF3

18 magnesium iodide 41 BaCl2

19 manganese(II) iodide 42 NiCl2

20 manganese(IV) iodide 43 SCl2

21 vanadium(V) nitride 44 FeCl3

22 chromium(II) nitride 45 Li2O

23 calcium nitride 46 SO

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Topic 2-04a Ternary Ionic Compounds

Ternary ionic compounds are ionic compounds, so there is a cation (+) and anion (-) present in the compound.

Now, one or both of these ions is a polyatomic ion. A polyatomic ion is a group of atoms which, overall, has a certain charge.

For example, nitrate, NO3G has one nitrogen and three oxygen atoms together as a group, with a "-1" overall charge:

www.chem.uiuc.edu/webfunchem/ternary/ternary2.htm

Our polyatomic ion chart lists the names and formulas of many of these ions.

The process of writing chemical formulas and naming ternary ionic compounds is very similar to the processes learned for binary ionic compounds in the previous section. The big difference is that if morethan one of the polyatomic ion is needed in the formula, BRACKETS are used around the polyatomic ion's formula.

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Steps: Writing the Chemical Formula of a Ternary Ionic Compound (with a Polyatomic Ion) Step 1: From the given name, write the formula for the cation with its (+) charge. (Unless the

polyatomic ion is ammonium, NH4+, then the "+" ion will be a metal ion.)

Then write the formula of the anion and its (-) charge. This is likely to be the polyatomic ion part of the formula of the ternary ionic compound.

Step 2: Ask: Are the charges "equal and opposite"?If yes: then write the final answer by putting the two symbols together, "+" cation first, "-" anion last. Do not include the charges in your final chemical formula.

If no: then "criss cross" the charges to become subscript numbers (see examples). If morethan one polyatomic ion is needed, place brackets around the polyatomic ion before placingthe number outside of the brackets.Lastly, make sure that the final ionic formula is in lowest terms.

Sample ProblemWrite the correct chemical formula for:(a) strontium nitrate

(b) lead(II) oxalate

(c) ammonium sulfide

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(d) zinc borate

(d) ammonium hydrogen sulfate

(e) silver sulfite

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Worksheet 2-04a Writing Chemical Formulas TERNARYIONIC COMPOUNDSGive the correct chemical formulas for:

(1) rubidium nitrate _____________ (23) sodium hypochlorite ____________

(2) barium hydrogen carbonate _____________ (24) titanium(III) dichromate ____________

(3) zinc perchlorate _____________ (25) titanium(IV) dichromate ____________

(4) zinc chlorate _____________ (26) potassium borate ____________

(5) sodium chlorate _____________ (27) vanadium(V) acetate ____________

(6) zinc chlorite _____________ (28) aluminum cyanide ____________

(7) sodium chlorite _____________ (29) gallium nitrite ____________

(8) iron(II) hydrogen sulfate _____________ (30) lead(II) permanganate ____________

(9) iron(III) hydrogen sulfate _____________ (31) nickel(III) hydroxide ____________

(10) copper(I) hydrogen sulfate _____________ (32) magnesium phosphite ____________

(11) copper(I) hydrogen sulfite _____________ (33) beryllium bromate ____________

(12) copper(II) hydrogen sulfate _____________ (34) aluminum phosphate ____________

(13) magnesium hydroxide _____________ (35) lead(IV) sulfate ____________

(14) cadmium thiocyanate _____________ (36) copper(II) oxalate ____________

(15) lead(II) hydrogen carbonate _____________ (37) silver nitrite ____________

(16) cesium phosphate _____________ (38) iron(III) sulfite ____________

(17) cobalt(III) silicate _____________ (39) iron(III) phosphite ____________

(18) vanadium(IV) iodate _____________ (40) cadmium chlorate ____________

(19) silver dihydrogen phosphite _____________ (41) strontium nitrate ____________

(20) tin(IV) dihydrogen phosphate _____________ (42) sodium acetate ____________

(21) gallium bromate _____________ (43) nickel(II) sulfate ____________

(22) beryllium chromate _____________ (44) nickel(II) benzoate ____________

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Topic 2-04b Ternary Ionic Compounds, Part 2: Naming Compounds

Recall: A ternary ionic compound has two ions: a cation (+), and an anion (-). At least one of theions is a polyatomic ion.

Steps: How to Name a Binary Ionic CompoundStep 1: The cation (+) is the first ion in the formula. It is one of:

- main group metal (Group "A" metal). In this case, just use the metal's name, no Roman numerals.

- transition metal (Group "B" metal). In this case, the correct charge must follow the metal's name, using Roman numerals. To get the correct charge, work backwards from the total "-" and total "+" charge (see examples).

- transition metal exception (Group "B" metal, but does not need Roman numerals) The three transition metal exceptions are:

"Cd" is just "cadmium"; "Ag" is just "silver";"Zn" is just "zinc"... no Roman numerals needed in either of these names!

- the polyatomic ion, ammonium "NH4

+" is ammonium... it is the only polyatomic "+" cation that will appear in ionic compounds.

Step 2: The anion (-) is the last ion in the formula. It is one of:- polyatomic ion

Match the formula of the polyatomic ion to its name on the polyatomic ion chart. For example, nitrate, NO3G, is a polyatomic anion.

- monoatomic ion These would not be on the polyatomic ion chart; these would just come from changing the ending of the element to "-ide". This would be a one-atom ion, such as "nitride, N3G".

Important note: Never use the prefixes "di-, tri-, tetra-" for these ternary ionic compounds!

Sample ProblemWrite the correct chemical names for:(a) SrCO3

(b) AgNO3

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(c) Cu(NO2)2

(d) NH4Br

(e) Cs2SO3

(f) NiHPO4

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Worksheet 2-04b Naming Chemicals TERNARYIONIC COMPOUNDS

State the correct IUPAC name for the ionic formula given.(1) MnSO4 ____________________ (23) Cr(BrO3)2 ______________________

(2) Ag2SO3 ____________________ (24) Nb(HSO3)5 ______________________

(3) Mg(NO3)2 ____________________ (25) Cu(CN)2 ______________________

(4) Mg(NO2)2 ____________________ (26) Co(ClO4)2 ______________________

(5) V2(CO3)5 ____________________ (27) Pd(HCO3)4 ______________________

(6) Ti2(C2O4)3 ____________________ (28) Na3PO3 ______________________

(7) Zn(BrO ) 2 ____________________ (29) NiCrO4 ______________________3

(8) K3PO4 ____________________ (30) AgIO3 ______________________

(9) BaSiO3 ____________________ (31) Sc(NO3)3 ______________________

(10) KH2PO4 ____________________ (32) CaSO4 ______________________

(11) K2HPO4 ____________________ (33) CdSO4 ______________________

(12) Pd(C6H5COO)4 ____________________ (34) CrSO4 ______________________

(13) Ga(CH3COO)3 ____________________ (35) Sr(HSO3)2 ______________________

(14) NiCr2O7 ____________________ (36) Li3BO3 ______________________

(15) V(S2O3)2 ____________________ (37) Co3(PO4)2 ______________________

(16) Ca(OH)2 ____________________ (38) CsOH ______________________

(17) Cd(CH3COO)2 ____________________ (39) CuSO3 ______________________

(18) Al2(CrO4)3 ____________________ (40) Fe2(HPO4)3 ______________________

(19) CoCO3 ____________________ (41) Ag2SiO3 ______________________

(20) CsClO ____________________ (42) Cu(ClO4)2 ______________________

(21) FeSO4 ____________________ (43) Ca(MnO4)2 ______________________

(22) Be3(PO4)2 ____________________ (44) CsMnO4 ______________________

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Topic 2-05 Hydrated Ionic Compounds

Hydrated ionic compounds form from solutions of ionic compounds in water. Crystals form from the solutions, and these crystals have a known amount of water of crystallization trapped in its solid crystal. Accordingly, the chemical formula of a hydrated ionic compound has two parts: an ionic compound part and a water of crystallization part.

The classic example of a hydrated ionic compound: "copper(II) sulfate pentahydrate" This is commonly known as "bluestone", and is used by gardeners as a lawn treatment.

The formula of the compound is:CuSO 4 . 5H O

2

"copper(II) sulfate" "pentahydrate"

(ionic compound part) (water of crystallization part)FIVE water molecules lockedin the crystal of the ioniccompound = "pentahydrate"

The neat thing: adding heat to a sample of a hydrated ionic compound "drives off" the water and makes it anhydrous. Heat the above compound and you can make copper(II) sulfate. Then, add water, you get the "copper(II) sulfate pentahydrate" back. And if you're bored, you can heat it up again, and... again... and...

So...

RULE: To name a hydrated ionic compound, think of the compound has having TWO PARTS: an ionic compound part and a water of crystallization part.

Step 1: Look at the ionic compound part only; ignore the water of crystallization part. Name the ionic compound part "as you would" any other time.

Step 2: Look at the water of crystallization part only. Put the correct SI prefix (i.e. mono-, di- tri-) that matches the number of water molecules in the formula in front of the word "hydrate".

Sample ProblemGive the correct IUPAC name or formula for the following compounds:(a) silver sulfate monohydrate

(b) aluminum carbonate tetrahydrate

(c) CaSO3 . 6H2O

(d) MnO2 . 3H2O

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Worksheet 2-05a Naming and Formula Writing: Hydrated Ionic Compounds

Complete the following chart by providing either the chemical name or the chemical formula, as needed.

Chemical Name Chemical Formula1. magnesium sulfate heptahydrate __________________________

2. sodium carbonate decahydrate __________________________

3. ___________________________________ MgBr .6H O

2 2

4. ___________________________________ Cd(NO ) .4H O3 2 2

5. barium chloride dihydrate __________________________

6. zinc sulfate hexahydrate __________________________

7. ___________________________________ LiCl.4H O2

8. ___________________________________ CaF .3H2 O

2

9. ___________________________________ Na S O.5H O2 2 3 2

10. aluminum chloride hexahydrate __________________________

11. barium hydroxide octahydrate __________________________

12. ___________________________________ Ni(ClO ) .6H O3 2 2

13. sodium sulfate decahydrate __________________________

14. cobalt(II) sulfate tetrahydrate __________________________

15. ___________________________________ Fe(NO ) .9H O3 3 2

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Topic 2-06 Chemistry Review 1Terms: 11. noble gases 21. NH3

1. MSDS2. WHMIS (know all symbols) 12. actinide series 22. O33. mass by difference 13 lanthanide series 23. H2O24. homogeneous mixture 14. metals 24. binary ionic compound5. heterogeneous mixture 15. main group elements 25. cation6. alkali metals 16. group (family) 26. anion7. alkaline earth metals 17. period 27. ternary ionic compound8. transition metals 18. staircase 28. monoatomic ion9. semimetals (metalloids) 19. molecular compound 29. polyatomic ion10. halogens 20. H2O 30. hydrated ionic compound

Matching Terms ReviewMatch the above terms to the statements below. Not all terms will be used. No term is used twice.

(a) These metals, such as nickel (Ni) and copper (Cu), are in the "B" block of the periodic table. These elements usually require a Roman numeral to indicate its specific charge when in an ionic compound.

(b) These are the Group 1 (IA) metals, including sodium (Na) and potassium (K). These metals are very reactive.

(c) These are the Group 17 (VIIA) nonmetals, including fluorine (F) and bromine (Br). These are also very reactive.

(d) This is the chemical formula for ammonia.(e) This line separates the metals from the nonmetals in the periodic table.(f) This family includes neon (Ne) and helium (He), and are the least reactive elements in the

periodic table.(g) These are the Group 2 (IIA) metals, including magnesium (Mg) and calcium (Ca).(h) This is the term for a vertical column in the periodic table.(i) This is the term for a horizontal row in the periodic table.(j) This type of compound contains nonmetals only.(k) This type of ionic compound contains only two types of elements, in the compound as charged ions.(l) This type of ionic compound has water of hydration trapped within the ionic crystal.(m) This type of ionic compound contains three or more types of elements, within charged ions.(n) This is the term for a positive ion.(o) This is the term for a negative ion.(p) This is the chemical formula for hydrogen peroxide.(q) This is the chemical formula for ozone.

Questions to Answer1. A student has to get an accurate mass of CuCl2(s) measured in to a beaker. She first starts with

the chemical in a weigh boat at the balances, and obtains this “mass by difference” data:Mass of CuCl2(s) and weighing boat: 17.28g

2.18gMass of weighing boat after transfer:Mass of CuCl2(s) transferred::

(a) What mass of CuCl2(s) was transferred to the beaker?(b) After reading the value off of the calculator and recording the value of the CuCl2(s)

transferred to the beaker, the student only recorded one decimal place in her lab report. Her teacher reminded her that two decimal places would be needed here. What should be the

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correct value recorded in the lab report, and why are two decimal places required?(c) The student noticed that some of the CuCl2(s) was left behind on the weighing boat when

she transferred the solid to the beaker. Yet, the student was not bothered by this; she knew that she would have an accurate mass measurement from her lab data above. Explain why she had every reason to be confident in her accurate mass measurement.

2. Name each WHMIS symbol.

3. (a) What is a MSDS?(b) WHMIS and MSDS are both safety systems. In general, when would a:

(i) WHMIS be used instead of a MSDS? (ii) MSDS be used instead of a WHMIS?

4. (a) Define, along with an example: (i) homogeneous mixture (ii) heterogeneous mixture(b) What lab technique can be used to efficiently separate a solid / liquid mixture?

5. What are five pieces of evidence which can be observed to be able to conclude that a chemical change has occurred?

6. Complete the following chemical naming / formula writing chart using correct IUPAC chemical names or formulas, as needed. In each case, first identify the compound type as ionic (i), molecular (m), or hydrated ionic (h). If a chemical has a traditional name, then state the traditional name.

i, m, or h Chemical Formula IUPAC or Traditional Name

1 N2O2 Li2SO4

3

4 Cd(HCO3)2

5

6 O3

7 SI2

8

lead(II) nitrate octahydrate

oxygen

hydrogen peroxide9 tungsten(VI) oxide10 ammonia

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i, m, or h Chemical Formula IUPAC or Traditional Name11 zinc hydrogen phosphate

12 Mn(CO3)2

13 Al2O3

14 CuF2.6H2O

15 nickel(II) borate

16 dichlorine tetroxide

17 Pd(SCN)4

18 NH4H2PO3

19 tin(IV) silicate

20 magnesium dichromate pentahydrate

21 nitrogen

22 Fe2(CrO4)3

23 B2O4

24 P4

25 dihydrogen disulfide

26 cobalt(II) chloride tetrahaydrate

27 F2

28 sulfur

29 gallium hydroxide

30 KNO2

31 vanadium(IV) phosphide

32 Ag2S. 6H2O

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Topic 2-07 Acids, Bases and Salts

Acids and bases are literally all around us in our daily lives.

Consider:Common acidic substances include:- Vinegar is dilute acetic acid (______________________);- phosphoric acid (_________________) gives cola soft drinks a tart taste;- lactic acid causes the 'burn' in your legs after exercising; found in sour milk and some cheeses.

Common basic substances include:- garden lime, calcium carbonate, (_________________) is placed on grass to neutralize acidic

soils and cut down on moss, or on baseball fields to mark the baselines;- sodium hydrogen carbonate (___________) is baking soda, which is used in baking and as an

air freshener;- chemical cleansers for unclogging drains (i.e. Drano®) contain high concentrations of

sodium hydroxide (______________), a corrosive strong base at high concentrations.

So... these chemicals are obviously useful, giving credence to our study of acids and bases. Yet...

How is an 'acid' or a 'base' defined?There are TWO WAYS to define an acid or a base, using either:1) chemical tests, or "operations"2) theory, using chemical equations.

OPERATIONAL DEFINITION of ACIDS and BASESNotice the difference in the behaviour between an acid and a base for each operation.The total set of observations for the tests define an acid or a base.

Chemical Test Acid behaviour Base behaviour(a.k.a. "Operation")

effect on litmus

pH test

taste

electrical conductivity

reaction with metals

reaction with each other

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When an acid neutralizes a base, a salt is produced. We define:

salt: any ionic compound produced by an acid-base neutralization.Note: "salt" is not always "sodium chloride" (i.e. table salt) ... though it can be.

Sample Problem:Write the chemical reaction which occurs between solutions of hydrochloric acid, HCl(aq) and sodium hydroxide, NaOH(aq) base. Water and an ionic compound are produced.

Solved:

What are some applications of acid-base neutralizations?- Neutralizing acidic soils

- Fish tank acidity:

- Antacids:

- Baking:

- Accident Response:

Questions to Answer:1. A solution does not conduct electricity. Is the solution acidic, basic or neither? Explain your

choice.

2. A clear colourless solution conducts electricity. Is this sufficient information to classify the substance as an acid or a base?

3. Substance X conducts electricity and tastes sour. When a piece of magnesium metal is added to substance X, bubbles are given off.(a) Is substance X acidic, basic, or neither? Explain.

(b) How could litmus paper be used to test your choice in (a) above?

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Topic 2-08 Chemical Reactions - Introduction

Chemical reaction: one or more new substances (with new chemical and physical properties) are produced from starting materials.

Question: Which is a chemical reaction below, #1 or #2, or both?

#1. H2O(s) ÿ H2O(l)

#2. Na(s) + H2O(l) ÿ H2(g) + NaOH(aq)

Answer:

Writing Chemical Equations - Rules and SymbolsA chemical reaction has:

- reactants (a.k.a. "reagents") on the LEFT, Next comes the ARROW, which points to the products on the RIGHT.

- the CORRECT chemical formulas are needed. "Close" isn't good enough! :)

- if known, the physical state of the chemical is given AFTER its formula, using:

solid = (____)

liquid = (____)

gas= (____)

aqueous = (____) This means that the substance is dissolved in water,

an "aqueous solution".

- If a chemical formula written ABOVE OR BELOW the arrow, it is a _______________. A catalyst is a substance that speeds up a chemical reaction without being used up or produced.

- If heat is added to the reaction, then the symbol found above the arrow is a __________.

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Sample Problems - Writing Chemical Reactions Read the chemical reaction below and then describe the reaction in a sentence or two.

(a) Mg(s) + AgNO3(aq) ÿ Ag(s) + Mg(NO3)2(aq)

Answer, (a):

MnO2

(b) H2O2(aq) ! H2O(l) + O2(g) Answer,

(b):

NOTE: The diatomics (i.e. the "7-Up elements") are really important now! "Oxygen gas" is always "O2(g)"; never just "O(g)"!

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Topic 2-09 Balancing Chemical Reactions

Consider the reaction: magnesium burns in oxygen (in the air) to produce magnesium oxide powder:

Mg(s) + O2(g) ! MgO(s)

Look at the total number of "O" atoms on the reactant side compared to the total number of "O" atoms on the product side...

As it stands now, it looks like we DESTROYED an "O" atom. Yet: A chemical reaction cannot create or destroy atoms!

THE LAW OF CONSERVATION OF MASS:Matter cannot be created or destroyed in a chemical reaction; thus the total mass of the reactants is ALWAYS equal to the total mass of the products.

So far, our reactions have been UNBALANCED; we have just written the skeleton equations - "bare bones" chemical equations with the CORRECT formulas, but the AMOUNTS of atoms are unbalanced.

We must BALANCE our skeleton equations to make them obey the law of conservation of mass.

BALANCING CHEMICAL REACTIONSStep 1: If not given, write a skeleton equation - the correct formulas for ALL reactants and

products, in "Reactants ÿProducts" form.

Step 2: Look for ONE element in the equation that is UNBALANCED between left and right;BALANCE it by PLACING A NUMBER IN FRONT of the WHOLE FORMULA; thenRECHECK the balance until ALL atoms are balanced.(Helpful hint: Watch out for polyatomic ions. If they stay together as a group between the left and right side, balance the polyatomic ions as a group.)

Final note: MAKE SURE YOUR BALANCING IS IN LOWEST TERMS.

Sample Problem:Write a complete balanced equation for the following.

(a) _____Al(s) + _____KCl(s) ! _____AlCl3(s) + _____K(s)

(b) _____CoCl3(aq) + _____AgNO3(aq) ÿ _____AgCl(s) + _____Co(NO3)3(aq)

(c) _____H2O2(aq) ÿ _____O2(g) + _____H2O(l)

NOTE: The balancing number that you place in front of a chemical formula is called a balancing coefficient.

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Worksheet 2-09a Balancing Chemical Equations, Sheet 1

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Worksheet 2-09a, ANSWER KEY Balancing Chemical Equations, Sheet 1

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Worksheet 2-09b Balancing Chemical Equations, Sheet 2

For more practice sheets (with answer keys) for balancing chemical equations, go to:http://chemistry.about.com/od/chemicalequations/a/How-To-Balance-Equations.htm

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Worksheet 2-09b, ANSWER KEY Balancing Chemical Equations, Sheet 2

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Topic 2-10 From Word Equations to Balanced Chemical Equations

Our goal: Given a chemical reaction, expressed in the names of the chemical reactants and products, we want to:

- write the chemical formula of each substance first;- balance the chemical reaction.

Sample Problem:Write balanced chemical equations for each of the following:(a) magnesium metal + oxygen gas ! magnesium oxide powder

(b) Copper(II) chloride solution reacts with aluminum foil to yield a solution of aluminum chloride and copper powder precipitate.

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Worksheet 2-10a From Word Equations to Balanced Chemical Equations

Write complete balanced chemical equations for each of the following. If descriptions of the states of matter ( (s), (l), (g), (aq) ) are included, then included the states of matter. Otherwise the states of matter are not required.

1. Solid zinc metal + lead(II) nitrate solution produces zinc nitrate solution + lead metal

2. aluminum bromide powder + chlorine gas produces aluminum chloride powder + bromine liquid

3. aqueous sodium phosphate + aqueous calcium chloride yield calcium phosphate precipitate+ sodium chloride solution

4. solid potassium chlorate, when heated, yields solid potassium chloride and oxygen gas

5. aluminum metal + hydrochloric acid (HCl(aq)) yield aqueous aluminum chloride and hydrogen gas

6. calcium hydroxide + phosphoric acid (H3PO4(aq)) yield calcium phosphate + water

7. copper + sulfuric acid (H2SO4(aq)) produces copper(II) sulfate + water + sulfur dioxide

8. hydrogen gas + nitrogen monoxide gas form liquid water and nitrogen gas

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Topic 2-11 "Word Equations" Review

Key Ideas:- reactants are on the left of the arrow; products on the right.- Watch out for the "7-Up" diatomic elements. When you see a substance described as

"oxygen", with no other element in that substance, then it is "O2", not just "O". The "7-Up club" are: nitrogen (N2), oxygen (O2), fluorine (F2), chlorine (Cl2), bromine (Br2), iodine (I2), and hydrogen (H2). Also watch out for just "sulfur" which is "S8" and "phosphorus" which is "P4". Also remember that when these elements are with another element in a compound, we go by the name of the compound to write the formula. So "nickel(III) fluoride" is NiF3, which is different from just "fluorine", which is "F2".

- For the states of chemicals, a chemical is:- a solid, (s), for the common descriptive words as powder, precipitate, foil. "Metal"

implies a solid, under usual lab conditions.- a gas, (g) for the common descriptive word of vapour.- an aqueous solution, (aq), for the descriptive words of solution, dissolved

If there is no description of the state of the chemical, the state can be omitted- "yields" means "produces".- If the reaction is heated, write a triangle (Ä) over the arrow.- If there is a catalyst given, write the chemical formula of the catalyst over the arrow.- Take your time writing the chemical formulas of each substance first; the last thing to do is

to balance the equation. If an equation does not balance, quite often one of the chemical formulas is incorrect.

Practice Problems: Write balanced chemical equations for each of the following. (Answers on next page.)

(a) iron(III) bromide solution + oxygen gas ! iron(III) oxide precipitate + bromine liquid

(b) potassium metal + iodine vapour ! potassium iodide powder

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(c) lead(II) nitrate solution + sodium fluoride solution ! lead(II) fluoride precipitate+ aqueous sodium nitrate

(d) When heated, zinc metal reacts with phosphorus powder to produce solid zinc phosphide.

(e) Sulfur reacts with chlorine gas to produce sulfur dichloride liquid.

(f) Hydrogen peroxide solution decomposes into liquid water and oxygen gas in the presence of MnO2 catalyst.

Answers(a) 4 FeBr3(aq) + 3 O2(g) ! 2 Fe2O3(s) + 6 Br2(l)(b) 2 K(s) + I2(g) ! 2KI(s)(c) Pb(NO3)2(aq) + 2 NaF(aq) ! PbF2(s) + 2 NaNO3(aq)

Ä(d) 6 Zn(s) + P4(s) ! 2 Zn3P2(s)(e) S8(s) + 8 Cl2(g) ! 8 SCl2(l)

MnO2

(f) 2 H2O2(aq) ! 2 H2O(l) + O2(g)

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Topic 2-12 Reaction Types 1:Simple Combination and Simple Decomposition Reactions

A simple combination (SC) reaction is also known as a simple composition reaction or even a formation reaction.

In this type of reaction, a compound is formed from its individual elements, as in:

Sample Problem 1:Magnesium metal burns in oxygen in the air to produce magnesium oxide powder.Write a word equation and a balanced chemical equation for the process.

Word Equation:

Balanced Chemical Equation(Note: Write the chemical formulas for each chemical first, then balance the equation last.)

... simple decomposition reactions follow...

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A simple decomposition (SD) reaction is essentially the opposite of the simple combination reaction which we have just seen.

In a simple decomposition reaction, a compound breaks into its individual elements, as in:

Sample Problem 2:When aluminum thiosulfate powder is heated, it decomposes into its elements. Write a word equation and a balanced chemical equation for the process.

Word Equation

Balanced Chemical Equation(Again, remember to write the chemical formulas first and balance the equation last.)

Sample Problem 3Given the reactions below, first classify the reaction type as either simple combination (SC) or simple decomposition (SD); then balance the reaction.

(a) Type: ______ _____ N2O4(g) ! _____ N2(g) + _____ O2(g)

(b) Type: ______ _____ Fe(s) + _____ N2(g) ! _____ FeN(s)

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Worksheet 2-12a Reaction Types 1:Simple Combination and Simple Decomposition Reactions

For each reaction given, first classify the reaction type as either simple combination (SC) or simple decomposition (SD). If necessary, write the chemical formulas of any missing chemicals. Lastly, balance the reaction.

Type

1. ______ Sulfur dioxide is produced by burning sulfur:

_____ S8(s) + _____ O2(g) ! _____ SO2(g)2. ______ In 1774, Joseph Priestly discovered pure oxygen gas from the reaction:

_____ HgO(s) ! _____ Hg(l) + _____ O2(g)

3. ______ Molten table salt is industrially transformed into molten sodium.

_____ NaCl(l) ! _____ Na(l) + _____ Cl2(g)

4. ______ Nitrogen from the air reacts with hydrogen to produce ammonia for fertilizers.

_____ N2(g) + _____ H2(g) ! _____ NH3(g)

5. ______ Hydrogen is used as a rocket fuel to propel a satellite into space.

_____ H2(g) + _____ O2(g) ! _____ H2O(g)

6. ______ Copper ore (CuO(s)) is decomposed to remove the copper metal.

_____ CuO(s) ! _____ Cu(s) + _____ O2(g)

7. ______ Barbecue charcoal (C(s)) undergoes incomplete combustion to produce deadly

carbon monoxide gas._____ C(s) + _____ O2(g) !

8. ______ Freshly cut lithium metal reacts with nitrogen from the air, producing lithiumnitride powder.

_____ + _____ ! _____ Li3N(s)

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Topic 2-13 Reaction Types 2:Single and Double Replacement Reactions

Single Replacement (SR) ReactionsIn a single replacement (SR) reaction, an element reacts to replace another element within a reactant compound.

Format:

Sample Problem 1In the blank provided under each chemical, identify "element" and "compound" chemicals. Then, balance each single replacement reaction.

(a) _____ Zn(s) + ____ HF(aq) ! _____H2(g) + _____ ZnF2(aq)______________ _____________ ____________ _____________

(b) _____ FeCl3(aq) + ____ I2(s) ! _____FeI3(aq) + _____ Cl2(g)

______________ _____________ __________ ___________

Double Replacement (DR) ReactionsIn a double replacement (DR) reaction, two ionic compounds react to form two new ionic compounds, as the "+" and "-" ions 'change partners'.

Format:

Sample Problem 2Balance the double replacement reaction below.

_____ Na2S(aq) + ____ AgNO3(aq) ! _____Ag2S(s) + _____ NaNO3(aq)

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Sample Problem 3Identify each reaction below as being either single replacement (SR) or double replacement (DR). Then, balance the reaction.

Type

(a) ___ K2CO3(aq) + ____ CaCl2(aq) ! ____KCl(aq) + ____ CaCO3(s)

(b) ___ Ni(NO3)2(aq) + ____ Li(s) ! ____Ni(s) + ____ LiNO3(aq)

(c) ___ Na(s) + ____ H2O(l) ! ____ NaOH(aq) + ____ H2(g)

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Worksheet 2-13a Reaction Types 2:Single and Double Replacement Reactions

Identify each reaction below as being either single replacement (SR) or double replacement (DR).Then, balance the reaction.

Type

(a) ___ Na(s) + ____ HCl(aq) ! ____ NaCl(aq) + ____ H2(g)(b) ___ Fe(NO3)3(aq) + ____ Mg(s) ! ____Fe(s) + ____ Mg(NO3)2(aq)

(c) ___ CsBr(aq) + ____ F2(g) ! ____ CsF(aq) + ____ Br2(l)

(d) ___ K2O(aq) + ____ CuCl2(aq) ! ____CuO(s) + ____ KCl(aq)

(e) ___ Li(s) + ____ H2O(l) ! ____ LiOH(aq) + ____ H2(g)

(f) ___ Sc(s) + ____ BeSO4(aq) ! ____ Sc2(SO4)3(aq) + ____ Be(s)

(g) ___ AgNO3(aq) + ____ NaCl(aq) ! ____ AgCl(s) + ____ NaNO3(aq)

(h) ___ K(s) + ____ GaF3(aq) ! ____Ga(s) + ____ KF(aq)

(i) ___ MgBr2(aq) + ____ F2(aq) ! ____MgF2(aq) + ____ Br2(l)

(j) ___ H2S(aq) + ____ Zn(aq) ! ____ZnS(s) + ____ H2(g)

(k) ___ Na3PO4(aq) + ____ Ni(ClO4)2(aq) ! ____Ni3(PO4)2(s) + ____NaClO4(aq)

(l) ___ Ba(OH)2(aq) + ____ HBr(aq) ! ____BaBr2(aq) + ____ H2O(l)

(m) ___ H2SO4(aq) + ____ LiOH(aq) ! ____Li2SO4(aq) + ____ H2O(l)

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Topic 2-14 Hydrocarbon and Carbohydrate Complete Combustion

Hydrocarbons contain two atoms only: _________________________

Carbohydrates contain three atoms: ___________________________

Hydrocarbons are common fuels:

C3H8(g): ________________________

C4H10(g): ________________________

C8H18(l): ________________________

C25H52(s): ________________________

"Combustion" means "burning". When hydrocarbons undergo complete combustion, there are only two compounds produced: carbon dioxide, CO2(g) and water vapour, H2O(g).

In general, for the hydrocarbon "CxHy", the complete combustion reaction is:

Our goal will be to balance the complete combustion reaction of any hydrocarbon or carbohydrate.

STRATEGY: Balancing Hydrocarbon (CxHy) Complete Combustion ReactionsStep 1: Balance the C and H atoms first.

Step 2: Get the total oxygen atoms, for the right side of the equation.Two possible scenarios will occur now.

If this total oxygen atoms is an even number, then balance the O2(g) on the reactant side. Done.

orIf this total oxygen atoms is an odd number, then double up every balancing number except the O2(g), then balance the O2(g) last.

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Sample ProblemEach reactant given undergoes complete hydrocarbon combustion. Write the chemical equation for the complete combustion and balance the equation.

(a) C5H12(l)

(b) C4H10(g)

Practice ProblemsBalance each complete combustion reaction.

(a) _____ C6H12(g) + _____ O2(g) ! _____ CO2(g) + _____ H2O(g)(b) _____ C6H14(g) + _____ O2(g) ! _____ CO2(g) + _____ H2O(g)

(c) _____ C6H12O6(s) + _____ O2(g) ! _____ CO2(g) + _____ H2O(g)

(d) _____ C7H16(g) + _____ O2(g) ! _____ CO2(g) + _____ H2O(g)

(e) _____ C2H6(g) + _____ O2(g) ! _____ CO2(g) + _____ H2O(g)

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Worksheet 2-15 Summary: The Five Main Reaction Types

Classify each reaction as one of the five main reaction types: simple combination (sc), simple decomposition (sd), single replacement (sr), double replacement (dr), or complete hydrocarbon combustion (hc) in the blank to the left of the question number. If a reaction does not fit any of these types, then classify it as "other" (o). Then, balance the chemical reaction.

Type1. ___ Cu(s) + ____ O2(g) ! ____ CuO(s)

2. ___ H2O(l) ! ____ H2(g) + ____ O2(g)

3. ___ Fe(s) + ___ H2O(l) ! ____ H2(g) + ____ Fe3O4(s)

4. ___ AsCl3(aq) + ___ H2S(aq) ! ____ As2S3(s) + _____HCl(aq)

5. ___ CuSO4(s) ! ____ Cu(s) + ____ S8(s) + ____ O2(g)

6. ___ Fe2O3(s) + ___ H2(g) ! ____ Fe(s) + ____ H2O(l)

7. ___ CaCO3(s) ! ____ CaO(s) + ____ CO2(g)

8. ___ Fe(s) + ___ S8(s) ! ____ FeS(s)

9. ___ H2S(s) + ___ KOH(aq) ! ____ HOH(l) + ____ K2S(aq)

10. ___ NaCl(s) ! ____ Na(s) + ____ Cl2(g)

11. ___ Al(s) + ___ H2SO4(aq) ! ____ H2(g) + _____Al2(SO4)3(aq)

12. ___ H3PO4(aq) + ___ NH4OH(aq) ! ____ HOH(l) + ____ (NH4)3PO4(aq)

13. ____ C3H8(g) + _____ O2(g) ! _____ CO2(g) + _____ H2O(g)

14. ___ Al(s) + ___ O2(g) ! ____ Al2O3(s)

15. ____ CH4(g) + _____ O2(g) ! _____ CO2(g) + _____ H2O(g)

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Topic 2-16 Reaction Rates

Some chemical reactions may be fast. For example, a fast reaction would be:

Some chemical reactions may be slow. For example, a slow reaction would be:

"Reaction rate" is the _______________________ of a chemical reaction; the speed in which reactants get converted in to products.

Different factors can affect the speed of a reaction. For Science 1206, we will consider

Factors Affecting Reaction Rate:1. Addition of Light or _____________2. Reactant Concentration3. Reactant Surface ______________

The details:

1. Addition of Light or HeatLight: Some reactions depend upon light to occur efficiently.

Example: photosynthesis in plants.

Heat: In general, reactions are faster when heat is applied. Consider:H2SO4(aq) + CaCO3(s) ! CO2(g) + CaSO4(s) + H2O(l) Notice the

carbon dioxide gas product. When the sulfuric acid (H2SO4(aq)) is warmed, the rate (or speed) of the carbon dioxide production is faster.This is because the warmed reactants have more energy, and can react and make the products at a faster rate than when colder.

When the above reaction was done in class:Trial 1: room temperature acid reacted to fill a test tube with CO2(g) in a

time of: __________________.

Trial 2: warmed acid, at ___________EC, reacted to fill the same size testtube with CO2(g) in a time of: __________________.

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2. Concentration of a Reactant "Concentration" is the amount of reactant in a given ___________________. (Think: "concentrated" orange juice has a lot of orange contained within it, and the "concentrated" orange juice needs to be watered down before it is used.)

The higher the concentration of a chemical reactant, the more reactant molecules are available to react in a given volume. With more reactants available to react, the faster the reaction.

Consider the same reaction as above:H2SO4(aq) + CaCO3(s) ! CO2(g) + CaSO4(s) + H2O(l)

If 20mL of H2SO4(aq) is used in this reaction, it will have a certain speed. If the reaction is run again, but 10mL of H2SO4(aq) acid is watered down by 10mL of water (to make 20mL of diluted acid solution) the reaction using the diluted acid will be slower than the reaction using the concentrated acid.

When the above reaction was done in class:Trial 1: non-diluted acid reacted to fill a test tube with CO2(g) in a time of

___________________.

Trial 2: acid diluted in half concentration reacted to fill a test tube with CO2(g) in a time of ___________________.

3. Surface Area of a ReactantA solid (s) reactant can be reacted as "chunks" or as a fine "powder". The chunk would have a low exposed surface area to react; the powder would have a high exposed surface area to react.The higher the surface area of a solid reactant, the faster the reaction rate.

Consider the same reaction as above:H2SO4(aq) + CaCO3(s) ! CO2(g) + CaSO4(s) + H2O(l)

If the solid CaCO3(s) is left as a chunk, the reaction is slower.If the solid CaCO3(s) is powdered, the reaction is faster.

When the above reaction was done in class:Trial 1: a "chunk" of chalk reacted to fill a test tube with CO2(g) in a time of

__________________________.Trial 2: powdered chalk (high surface area) took only ___________________!

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Worksheet 2-16a Questions to Answer: Reaction Rates

1. The instructions on a particular brand of pizza dough states that once the flour, baking powder and water are mixed into dough, the dough is to be placed in a warm area for 15 minutes for the dough to rise before completing the pizza. Why would a warm area be important?

2. When camping, why would a fire be started using finely chopped kindling compared to using just blocks of wood at the start?

3. Why do you think some medications state in the instructions: "Do not chew before swallowing"?

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Topic 2-17 Chemistry Review 2Terms: 9. balanced equation 17. double replacement

1. acid2. base 10. balancing coefficient 18. hydrocarbon combustion3. pH scale 11. catalyst 19. limewater test4. neutralization 12. triangle (symbol) 20. litmus paper test5. salt 13. precipitate 21. hydrogen gas test6. reactants 14. simple combination (formation) 22. reaction rate7. products 15. simple decomposition8. law of conservation of mass 16. single replacement

Matching Terms ReviewMatch the above terms to the statements below. Not all terms will be used. No term is used twice.

(a) A substance with a pH above 7, which turns red litmus blue. Its general chemical formula is "MOH(aq), for a metal hydroxide solution.

(b) A substance which is produced when an acid and base neutralize each other.(c) A substance which has a pH below 7 and produces bubbles of hydrogen gas when it reacts with a metal.

Its general chemical formula is "HX(aq)", for a hydrogen cation containing solution.(d) The substances which are found on the left side of an arrow in a chemical reaction.(e) A scale which measures acidity, and ranges from 0 to 14.(f) The substances which are formed or "yielded" in a chemical reaction.(g) An idea which states that the total mass of the reactants in a chemical reaction must equal the total mass

of the products.(h) A number placed in front of a chemical in a balanced reaction, which assists in balancing the atoms in

the equation.(i) A solid produced in a chemical reaction.(j) A substance which speeds up a chemical reaction. Its formula may be written above the arrow in a

chemical equation.(k) When heat is added to a chemical reaction, this may be written above the arrow.(l) The reaction type which is "compound ! element + element".(m) The reaction type which is "element + element ! compound".(n) The reaction type which is "compound + compound ! new compound + new compound".(o) The reaction type which involves the burning of a compound containing carbon and hydrogen only.(p) The reaction type which is "element + compound ! new element + new compound".(q) A chemical test for an explosive gas, which involves having a lit wooden splint "pop".(r) A chemical test for carbon dioxide gas (CO2(g)), whereby a solution of calcium hydroxide produces a

white precipitate of calcium carbonate when CO2(g) is present.

Questions to Answer1. From the following information, determine whether the substance described is ionic, molecular, acid or

base. Briefly explain your reasoning.(a) Substance V is a bright green powder. It dissolves easily in water, and the resulting clear green

solution is an excellent conductor of electricity.(b) Substance W is a clear colourless liquid with a odour similar to gasoline. When placed in water,

the substance sits atop the water, and does not conduct electricity.(c) Substance X turns litmus paper blue.

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1. (continued)(d) Substance Y is a white solid which dissolves easily in water, but the resulting clear colourless

solution does not conduct electricity.(e) Substance Z turns litmus paper red.

2. How does an acid and a base behave when: (a) a metal is added to the solution?(b) its conductivity is tested?

3. In the reaction below, 15.0g of NO(g) reacts with 9.50g of F2(g). If 7.00g of N2(g) is produced, what mass of F2O2(g) is also produced?

2 NO(g) + F2(g) ! N2(g) + F2O2(g)

4. Balance the following equations.

(a) _____ Ga(CN)3 + ______ Li2SO4 !_____ Ga2(SO4)3 + ______ LiCN(b) _____ Zn + ______ O2 ! ______ ZnO

(c) _____ Mg + ______ KOH !______ Mg(OH)2 + _______ K

(d) _____ C6H14 + ______ O2 !______ CO2 + _______ H2O

(e) _____ CsOH ! _______ Cs + _______ H2 + ________ O2

(f) _____ Al + ______ NaHS ! _______ Al(HS)3 + _______ Na

(g) _____ S8 + ______ GaP ! _____ Ga2S3 + ______ P4

5. For the information given in each the following, write a balanced chemical equation.(a) sodium phosphate + ammonium hydroxide ! sodium hydroxide + ammonium phosphate(b) fluorine + nickel(III) oxide ! nickel(III) fluoride + oxygen(c) When heat is added to a solid sample of silver chloride crystals, solid grey silver metal and a

pale yellow gas, chlorine, results.(d) When beryllium metal is placed in liquid water, bubbles of hydrogen gas are produced along

with beryllium hydroxide solution.

6. For each reaction below:(i) Classify the reaction type as one of:

simple combination (sc) single replacement (sr) hydrocarbon combustion (hc)simple decomposition (sd) double replacement (dr)

(ii) Balance the reaction.(a) Type: ______ _____ FeCl3 ! _____ Fe + _____ Cl2

(b) Type: ______ _____ Ca + _____ Na2O ! _____ CaO + _____ Na

(c) Type: ______ _____ C7H16 + _____ O2 ! _____ CO2 + _____ H2O(d) Type: ______ _____ Li + _____ Cl2 ! _____ LiCl(e) Type: ______ _____ N2 + _____ Ni2O3 ! _____ NiN + _____ O2

(f) Type: ______ _____ H2SO3 + ___ KOH ! _____ H2O + _____ K2SO3

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7. In each case, state which reaction would be faster, and briefly explain your response.(a) Reaction 1: 2 Fe(s) + O2(g) ! 2 FeO(s) vs. Reaction 2: 2 Fe(s) + O2(g) ! 2 FeO(s)

fine iron wire iron plate(b) Reaction 1: 2 H2O2(aq) ! 2 H2O(l) + O2(g) vs. Reaction 2: 2 H2O2(aq) ! 2 H2O(l) + O2(g)

60EC 90EC

8. Some pain reliever medications are marketed as "fast acting capsules". Do you think that the medication inside the capsule would be a large single tablet or a large number of tiny beads?

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