Practice Exam for Grade 11

2005 June Exam Information & Hints

Exam Format: for June 2005 Exam

Openning Hints

Short answer questions will be done in the space provided. Again, try to make up your own questions.
Charts to be filled in: ask yourself "what type of questions would be answered in a chart?" Most obvious is NOMENCLATURE.

Extend response requires that you apply chemical theory and principles to explain an observed phenomena. Try to think of such phenomena; such as the colours of the hydrogen spectrum, how a barometer works, why a refrigerator works, why a titration works etc.

The lab question(s). Check out ALL the labs you did. The section will not be a lab you did directly but one based or follows exactly one that you DID do.
Most labs we did involved measurements and calculations. A lab such as flame tests is just a little too simple for the full 20 marks. A good example would be a titration lab or an ion separation activity, where you must know the apparatus used, chemical needed and why do the lab in the first place.

Exam Hints

• Nomenclature
• Mole gram conversions. Avogadro's number
• Section 2.12 in the text (very few took me up on this last semester) Atomic theory
• page 331
• Electron configurations: electrons in their shells.
• Ionization potential, electonegativity, atomic/ionic radii, electron affinity & their respective trends
• Bonding: Ionic, Covalent, PolarCovalent, Lewis Dot diagrams, Molecular shape (page 155)
• Empirical & True formula calculations, Percentage Composition
• Isotopes: Calculating relative atomic mass or determining % abundance of each isotope.
• How to recognize when a chemical change takes place as opposed to just a physical change. Do you know what a catylst is and an example of one.
• Types of reactions [5 given types] Balancing equations
• Kinetic Molecular Theory and using theory to explaining Gas Laws
• Gas Law calculations; know the Laws both numerically and for definition purposes.
• Stoichiometry: using the balanced equations with grams, moles and volumes (both at STP and not at STP)
• Know how to read a solubility curve
• Solutions: Definitions Precipitations, doing the math, how to dilute a stock solution to a required concentration.
  The dilution formula C_c x V_c = C_d x V_d
• Electrolytes; weak and strong As applied to acids and bases
• Acid Base theory. Titrations: the titration formula is exactly like the dilution formula
• Know how to calculate an experimental error in percent.
• Naming and writting formula for hydrocarbons
• Calorimetry and the types of thermodynamic reactions
  Using the equation Q = mΔtc

Know all of this stuff and you should do really really well.

This final exam is for you to practice on and see if you know everything you should.
Please note that this so called exam would be rather longer than any real exam you would be given. My purpose is to hit every type of question you would see.
An answer page will eventually be provided. Multiple choice answer key at the bottom.

Part A Multiple Choice

1. The atom phosphorus has how many neutrons?
   a) 31, b) 30, c) 15, d) 16, e) 17
2. Zinc and sulphur react to produce
   a) zinc sulfate, b) zinc sulpite, c) zinc sulfide, d) zinc sulfur.
3. Which of these elements has the largest radius?
   a) calcium, b) selenium, c) krypton, d) potassium
   
4. Potassium chlorate is heated and decomposes. What is the product that is left behind?
   a) potassium, b) chlorine, c) potassium chlorite, d) potassium hypochlorite, e) potassium chloride
   
5. How many atoms are in the molecule Fe₂(HPO₄)₃
   a)4, b) 8, c) 16, d) 18, e) 20
   
6. The Gas Law Constant has a value of a) 6.022x10²³, b) 3.14, c) 8.314, d) 8.413
   
7. A supersaturated solution has
   a) more solute in it than solvent, b) very concentrated at that temperature
   c) more solute dissolved per unit solvent that can normally be dissolved at that temperature
   d) a solution that cannot dissolve any more solute unless you heat up the solution
   
8. Which of the following is not a physical change?
   a) An ice cube is heated and begins to melt
   b) A piece of copper wire is heated
   c) Potassium chlorate is heated
   d) When heated an oil's viscosity decreases
   
9. Which of these atoms has the greatest electronegativity
   a) chlorine, b) bromine, c) iodine, d) oxygen, e) sodium
   
10. Sulphuric acid reacts with ammonium hydroxide. This reaction is classified as a
    a) a neutralization reaction, b) a single displacement reaction, c) a double displacement reaction
    d) a replacement reaction, e) both a) and c) are correct
    
11. When vinegar turns to a vapour the process is called
    a) condensation, b) evaporation, c) sublimation, d) distillation, e) viscosity.
    
12. Which of the following is not a physical property?
    a) viscosity, b) reactivity with an acid, c) magnetic, d) volume, e) thermal conductivity.
    
13. If two elements have the same number of protons,yet different numbers of neutrons they are considered to be
    a) isoelectronic, b) isotopes, c) ionic, d) a transition metal, e) radioactive.
    
14. How many neutrons does ⁵⁵Mn have?
    a) 25, b) 30, c) 35, d) 55, e) 80.
    
15. What is the valence of antimony?
    a) 3, b) 5, c) 3 and 5, d) 2 and 4, e) 2,3 and 5
    
16. How many outer shell electrons does nickel have?
    a) 1, b) 2, c) 3, d) 4, e) 5.
    
17. What law describes a pressure volume relationship?
    a) Boyle's law, b) Charles' Law, c) Dalton's Law, d) Ideal Gas Law, e) Gay-Lussac's Law.
    
18. If the mass and volume are kept constant, what happens to the temperature if the pressure of a gas is decreased?
    a) will increase, b) will decrease, c) will remain constant, d) will vary inversely with the pressure,
    e) depends on the volume.
    
19. How many moles is 12.7 g of chlorine gas at STP?
    a) 0.179, b) 0.358, c) 0.576, d) 2.90, e) 5.59.
    
20. Iron reacts in hydrochloric acid to produce iron (II) chloride and hydrogen gas. This reaction is classified as
    a) a metathetic reaction, b) a double displacement reaction, c) a single displacement reaction,
    d) an addition reaction, e) an oxidation reaction.
    
21. Which of the following is NOT a chemical reaction?
    a) zinc in hydrochloric acid, b) oxidation, c) plant growth, d) salt is added to ice, e) silver tarnishes in air.
    
22. How many grams of SnCl₂ are in 0.5 moles?
    a) 0.5 M b) 94.85 g, c) 189.7 g, d) 263.2 g, e) 379.4 g.
    
23. How many electons are present in the sulfide ion?
    a) 14, b) 15, c) 16, d) 17, e) 18.
    
24. Which of these has the greatest electronegativity?
    a) Na, b) K, c) Ar, d) Br, e) Cl.
    
25. 3 moles of any gas at STP has a volume of
    a) 7.46 L, b) 14.9 L, c) 22.4 L, d) 44.8 L, e) 67.2 L.
    
26. Safety in the lab depends on
    a) wearing your goggles, b) reading the lab exercise, c) listening to the instructions, d) being alert, e) all of these.
    
27. A sample of titanium (IV) oxide contains 45.7% titanium. How much titanium is present in a 142.7 g sample of this oxide?
    a) 6521 g, b) 312.3 g, c) 67.78 g, d) 65.21 g, e) 3.213 g.
    
28. Bohr diagrams are useful in
    a) determining the electron structure of an atom.
    b) explaining the valence of an atom.
    c) determining which atom/ion pairs are isoelectronic with each other.
    d) explaining the colours of the hydrogen spectrum.
    e) all of these.
    
29. The N shell of an atom has a maximum of x electrons. The value for x is
    a) 8, b) 18, c) 25, d) 32, e) 64.
    
30. Which of the following is an alkali metal?
    a) potassium, b) strontium, c) vanadium, d) aluminum, e) argon.
    
31. Which of these best exemplifies a polar covalent bond?
    a) hydrochloric acid, b) sulfuric acid, c) chlorine gas, d) sodium chloride, e) methane.
    
32. Which of these atoms is the smallest?
    a) Ca, b) Cr, c) Ge, d) As, e) Br.
    
33. How many lone (non-bonding) pairs does sulfur have?
    a) 1, b) 2, c) 3, d) 4, e) all of these.
    
34. An acid is a material that
    a) loses an electron, b) donates a proton, c) gains a proton, d) gains an electron, e) has a pH.
    
35. Which element does NOT belong in this list?
    a) Cl, b) F, c) H, d) I, e) At.
    
36. Which of the following is a metalloid?
    a) Br, b) Ge, c) Sn, d) Gd, e) Xe
37. At constant volume, the pressure of a gas at STP will decrease if the temperature of the gas is changed to
    a) 273 K b) 283 K c) 263 K d) 373 K
38. To separate lead⁺²ions from silver ions which cation best does the job? a) chloride, b) hydroxide, c) sulfate, d) acetate

Part B Fill in the Blanks

1. How many neutrons in the osmium atom? ________________
   
2. What is the concentration of a solution containing 4.5x10^-2 moles of sodium sulfate in 55 ml of solution ______________
   
3. How many atoms are there in 0.045 moles of plumbic chlorate? ____________ atoms.
   
4. How many grams are there in 7.88 x 10^-3 moles of iridium (III) dihydrogen phosphite? ___________ grams
   
5. What are the valence numbers for the antimony atom? __________
   
6. What family of metals is the most reactive? __________________
   
7. Which law predicts how pressure and temperature are related? ___________________________
   
8. A supersaturated solution is one in which ______________________________
   
9. How many grams in ¾ mole of cupric sulfite? ___________ grams.
   
10. Why is the chlorine ion bigger than the chlorine atom? ________________________
    
11. What is the shape of the water molecule? _______________
    
12. If the pressure of a balloon is doubled, what must happen to its volume? [Temperature remains constant] ______________
    
13. How many electron(s) can magnesium lose to phosphorus? _______________
    
14. Sketch a Bohr diagram for silicon and cobalt
    
15. When sodium is put in water the observations are . .
16. Calcium in water produces a ______________ which turns bromothymol blue a _____________ colour.
17. The Lewis dot diagram for sulfur is _______ .
18. Sodium chloride (aq) added to silver nitrate (aq) produces a ____________ . State what is observed, not the products.
19. Polar covalent molecules have electronegativity differences between ________ and __________ .
20. An example of a weak electrolyte is ________________ . How can this be shown experimentally?
21. The pH of a solution that has a hydrogen ion concentration of 4.67x10^-4 is ______________
22. How many neutrons in the palladium ¹⁰⁷Pd atom? _________
23. What is the formula of chlorine gas? ___________
24. What is the volume of 22.0 g of carbon dioxide at STP? _________
25. Write the expression for the dissociation of acetic acid. ________________
26. As you go across a period the _______________ generally increases.
27. Germanium has ________ electrons in its last shell.
28. Methyl orange changes colour at what pH range? __________

Part C: Written Responses

1. Sketch Bohr diagrams for these atoms; Chlorine, zinc, nitrogen, nickel, sulfide ion, strontium ion.
2. Using Lewis dot diagrams show how the two atoms i) calcium and chlorine and ii) sulfur and aluminum, bond together. Write equations that show electron transfer
3. Define each of the following terms:
   a) Charles' Law, b) electronegativity, c) solubility, d) Octet Rule, e) Law of Constant Composition,
   f)calorimetry, g) Chemical property, h) STP, i) end point, j) cation, k) solute, etc this list could go on and on.
4. Using Kinetic Molecular Theory explain the following: a) Boyle's Law, b) Dalton's Law of Partial Pressure, c) Why the mass of a molecule can be ignored in pressure calculations.
5. Outline how you would determine the concentration of a solution that has an unknown amount of KOH in it. State necessary glassware and equipment needed and any chemical reagents necessary to make the determination.
6. How would you experimentally tell the difference between a weak and strong acid. Give an example of each.
7. A solution contains the ions Pb⁺², Na⁺¹, and Ag⁺¹. Outline how you would go about separating these three ions.

Part D CHARTS
Charts would contain Nomenclature, Atom Shell Structure with p, n, e's, Acid \ Base | Indicator recognition.
Molecular sketches of hydrocarbons compounds eg. CH₃CH₂COOH
You must be able to balance equations (Insert required coefficients)

Part E Mathematical Problems: Note that there is repetion in these questions

1. The atomic masses of ⁶Li and ⁷Li are 6.0151 and 7.0160, respectively. Calculate the natural abundances of these two isotopes given the atomic mass of Li to be 6.941 amu.
   
2. What is the empirical formula of a compound which on analysis shows 69.9% iron and 30.1% oxygen ?
3. How many moles are there in a 25 mL solution which has a concentration of 5.98x10^-3mole/L?
   
4. A gas at 5.67^oC has a pressure of 99.7 kPa. If it is heated to 14.7^oC and its pressure increased to 102.6 kPa, find its new volume if it's initial volume is 1.45 L.
5. Determine the percentage composition of sulfur in the compound stannic sulfite.
6. What is the mass of 4.56L of propane (C₃H₈) at STP?
7. How many moles in 16.8 grams of zinc phosphate?
8. How many molecules in 3.5x10^-4moles of calcium chloride? Also how many atoms
9. If a gas at 17.5^oC has a volume of 2.45 L, is heated to 45.2^oC, calculate the new volume.
10. Calculate the percentage of chromium in the compound potassium dichromate.
11. A compound of ferrous nitrate has a mass of 4.87 g. Determine the mass of just the iron in this compound.
12. Determine the volume of 23.5 g of nitrous oxide (NO₂ at 98.7 kPa at 21.8^o
13. In a double displacement reaction of zinc chloride and silver nitrate, 25.7 grams of zinc chloride reacted completely. Determine how many grams of silver chloride was precipitated.
14. Given this reaction in which 4.57 g of magnesium react
    Mg + H₃ PO₄ ----> Mg₃(PO₄)₂ + H₂ If this reaction takes place at 24.7^oC and at 105.7kPa pressure, calculate the volume of hydrogen gas produced.
15. Given this reaction (NH₄)₂CO₃ + MgCl₂ ----> NH₄Cl + MgCO₃
    a) If 16.89 grams of ammonium carbonate react, how many grams of magnesium chloride are produced?
    b) How many moles of ammonium chloride are produced when 1.15 grams of magnesium chloride react?
16. Determine the temperature of 4.87 grams propane (C₃H₈, if its pressure is 165.5 kPa and it has a
    volume of 2.78 L
17. Given this reaction
    LiOH + CO₂ ----> Li₂CO₃ + H₂O
    If 24.5 g of lithium hydroxide react with 23.9 g of carbon dioxide determine the following
    a) the limiting reagent and b) how many grams of lithium carbonate are produced
18. How many grams of sodium hydroxide will be required to completely neutralize 3.56 x 10^-2 moles of sulphuric acid?
19. A solution of sulphuric acid has a concentration of 9.0 mol/L. How much of this solution must be taken to make a 200mL dilute solution of sulphuric acid with a concentration of 1.5 x 10^-2 mol/L ?
20. The analysis of a compound shows that it is made up of 21.9% sodium, 45.7% carbon, 1.90% hydrogen and 30.5% oxygen. What is the molecular formula of the compound, if its molecular mass is 210 u?
21. 65.0 grams of sugar (C₆H₁₂O₆ are burned in a calorimeter and the heat causes 200 g of water to rise from 15.6^oC to 28.4^oC. Calculate the molar heat of this reaction. Remember, molar heat refers to the heat produced if 1 mole os sugar was to react. In this problem only 65.0 g reacted. Complete combustion can be assumed

Answers: Multiple Choice Must still be reviewed errors are present.

1 - d

2 - c

3 - d

4 - d

5 - e

6 - b

7 - e

8 - c

9 - c

10 - c

11 - e

12 - a

13 - e

14 - b

15 - d

16 - b

17 - b

18 - c

19 - b

20 - a

21 - b

22 - a

23 - c

24 - d

25 - b

26 - e

27 - e

28 - e

29 - e

30 - d

31 - e

32 - d

33 - b

34 - a

35 - e

36 - b

37 - b

38 - c

39 - e

40 - b

41 - c

42 - c

43 - c

Last update May 2005

Answers to Fill in the Blanks

1. 190 - 76 = 114 neutrons
2. 0.82 mol/l
3. A high energy electron emmitted from an atom in radioactive decay.
4. 6.02 x 10²³ x 0.045 = 2.71 x 10²² molecules
   Number of atoms ==> 2.71 x 10²² x 17 atoms
5. Formula ==> Ir(H₂PO₃)₃ ==> formula weight 383.15 g/mol
   Mass ==> 435.19 x 0.00788 g
6. -3, +3, +5
7. alkalie metals
8. Guy-Lussac's Law
9. Has more solute dissolved in the solvent that the solution can normally hold at that temperature
10. Cu(HSO₃)₂ formula weight is 254.8 g/mol
    Mass of ¾ mole is 190.85 g
11. chlorine ion
12. bent V
13. Volume must decrease by a factor of 2. Volume is cut in half.
14. 2 electrons
15. N/A
16. Forms a ball and goes in circles on the surface of the water, some smoke produced, sodium gradually disappears. May burst in a yellow flame.
17. base, calcium hydroxide .... blue ....
18. N/A
19. white precipitate of silver chloride
20. 0.6 and 1.7
21. ammonium hydroxide
22. 3.33
23. 101 neutrons
24. Cl₂
25. CO₂ ===>44 g/mol. Number of moles 22/44 = 0.5 moles
    Volume 22.4L x 0.5 mol/L = 11.2 L
26. CH₃COOH _(aq) <====> H⁺ _(aq) + CH₃COO^-1_(aq)
27. ionization energy
28. 4 shells
29. pH value of approximately 4.