These questions may not be in the same order as your exam. The correct answers are underlined. Some characters were lost upon conversion to html.

1. All of the following are properties of oxygen. Which one is a physical property? (2pts)

(a) It supports combustion.

(b) It condenses to a liquid at —219°C and atmospheric pressure.

(c) It causes iron to rust.

(d) It reacts with calcium to produce calcium oxide, CaO.

(e) All of these are physical properties.

2. Which of the following is an extensive property of matter? (2pts)

(a) weight

(b) melting point

(c) specific gravity

(d) color

(e) density

3. Which statement is false? (2pts)

(a) A compound is a substance that can be decomposed by chemical means into simpler substances.

(b) All samples of a particular pure substance have the same composition and properties.

(c) An example of a homogeneous mixture is one prepared by mixing two liquids, ethyl alcohol (grain alcohol) and water.

(d) An example of a heterogeneous mixture is one prepared by dissolving the solid, sodium chloride (table salt), in the liquid, water.

(e) Different mixtures of the same two substances can have different compositions.

4. Which of the following is an intensive property of matter? (2pts)

(a) mass

(b) density

(c) volume

(d) weight

(e) heat capacity

5. Which answer includes all of the following that are physical changes and no chemical changes? (2pts)

I. the electrolysis of molten sodium chloride to produce metallic sodium and gaseous chlorine

II. the solidification of mercury by cooling

III. the reaction of hydrochloric acid with calcium carbonate

IV. the mixing of water with ethyl alcohol

V. cutting an iron bar into small pieces

(a) I and III

(b) II, IV, and V

(c) I and IV

(d) II, III, and V

(e) IV

6. Below is a list of common prefixes used in the SI and metric systems. Included with each is an abbreviation and meaning. Which set contains an error? (2pts)

(a) mega- M 106

(b) deci- d 10—1

(c) centi- c 10—2

(d) micro- m 10—6

(e) kilo- k 103

7. Stainless 316 is a steel alloy containing 17% Cr, 12% Ni, 3.0% Mo, and 0.10% C with the rest being Fe. What mass of iron (in kg) would be contained in 1000 kg of this alloy? (4pts)

(a) 68 kg

(b) 760 kg

(c) 580 kg

(d) 680 kg

(e) 780 kg

8. Liquid propane boils at 231K. What is its boiling point in °C ? (2pts)

(a) 42°C

(b) 315 °C

(c) —42°C

(d) 504°C

(e) —231°C

9. The formula for oxalic acid is (COOH)2. How many atoms does each molecule contain? (2pts)

(a) 6

(b) 4

(c) 8

(d) 10

(e) 5

10. A metal cube having a mass of 112 grams is dropped into a graduated cylinder containing 30.00 mL of water @ 25^oC. This causes the water level to rise to 39.50 mL. What is the Specific Gravity of the cube? (4pts)

(a) 2.86

(b) 11.8

(c) 10.8

(d) 3.74

(e) 10.6

11. If a sample of propane, C3H8, contains a total of 6.0 x 103 atoms of carbon, how many molecules of propane are in the sample? (3pts)

(a) 6.0 x 103

(b) 3.0 x 103

(c) 8.0 x 103

(d) 1.1 x 104

(e) 2.0 x 103

12. What is the percent by mass of sulfur in Al2(SO4)3? (3pts)

(a) 9.38%

(b) 18.8%

(c) 24.6%

(d) 28.1%

(e) 35.4%

13. From the following ionic compounds, choose the name-formula pair that is not correctly matched. (2pts)

(a) sodium sulfide Na2S

(b) ammonium nitrate NH4NO3

(c) zinc hydroxide Zn(OH)2

(d) sodium sulfate Na2SO3

(e) calcium oxide CaO

14. A 12.0-gram sample of Cr2(SO4)3 contains how many sulfur atoms? (3pts)

(a) 1.84 x 1022

(b) 1.53 x 1021

(c) 4.82 x 1021

(d) 6.67 x 1022

(e) 5.52 x 1022

15. What mass of calcium metal could be obtained from one kg of limestone that is 50.0% pure CaCO3? (No other calcium-containing compounds are present.) (4pts)

(a) 0.05 kg

(b) 0.2 kg

(c) 0.4 kg

(d) 0.5 kg

(e) 0.1 kg

16. A compound contains carbon, oxygen, and hydrogen. Analysis of a sample showed that it contained by mass 53.4% carbon and 11.1% hydrogen. What is the simplest formula for this compound? (4pts)

(a) CHO

(b) C2H5O

(c) C2H4O

(d) CH4O2

(e) C2H5O2

17. Calculate the molarity of a solution that contains 70.0 g of H2SO4 in 280. mL of solution. (3pts)

(a) 2.55 M

(b) 6.84 M

(c) 8.62 M

(d) 9.78 M

(e) 11.84 M

18. Glucose has a molecular weight of 180.2 g and an empirical formula CH2O. What is its molecular formula? (3pts)

(a) C8H4O5

(b) C6H12O6

(c) C12H22O11

(d) C10H12O3

(e) CH2O

19. If a reaction of 27.5 g of Fe with 63.1 g Cl2 produced 60.4 g of FeCl3, what was the limiting reactant and the percent yield? (4pts)

(a) Fe, 75.6%

(b) Fe, 62.8%

(c) Cl2, 41.8%

(d) Cl2,63.0%

(e) Fe, 37.8%

(a) 1

(b) 2

(c) 3

(d) 4

(e) 5

21. How many molecules of O2 would react with 56 C2H6 molecules according to the following balanced equation? (2pts)

(a) 196

(b) 392

(c) 112

(d) 50

(e) 784

22. How many moles of CaCO3 would have to be decomposed to produce 129 grams of CaO? (3pts)

(a) 1.75

(b) 1.86

(c) 2.00

(d) 2.25

(e) 2.30

23. What mass of 30.0% Ca(NO3)2 solution contains 60.0 grams of water? (3pts)

(a) 42.0 g

(b) 85.7 g

(c) 58.0 g

(d) 14.3 g

(e) 62.4 g

24. What mass of calcium carbonate, CaCO3, is required to react with 100. mL of 2.00 M HCl solution? (4pts)

(a) 5.00 g

(b) 10.0 g

(c) 15.0 g

(d) 20.0 g

(e) 23.0 g

Free Response Question: (Show ALL of your work!!!)

27. The molecular formula for a compound is CX₄. If 2.819 g of this compound contains 0.102 g of carbon, what is the atomic weight of X? (5pts)

0.102 g C * (1 mole/12.01g C) = 0.0084929 mol C

0.0084929 mol C * (4 mol X/1 mol C) = 0.03397 mol X

2.819 g CX₄ - 0.102 g C = 2.717 g X

2.717 g X / 0.03397 mol X = 80.0 g/mol