1. Chemistry Released Items
2001

2. Evaporate and then distill Evaporate and then condense
1. To remove the sand first then the salt from a mixture of sand and salt water, one combination of techniques you could use would be the first--
Evaporate and then distill
Evaporate and then condense
Filter and then evaporate
Filter and then condense 1 2 3 4 5

3. 2. Which is an example of a synthesis reaction?
HCl + KOH→KCl + H20
Pb(NO3)2 + 2HBr→PbBr2 + 2HNO3
C + O2→ CO2
Mg + H2SO4 → MgSO4 + H2 1 2 3 4 5

4. 3. What would be the product(s) of this reaction? 3MgO + 2Al →
2Mg3Al2O3
Mg3Al2 + 3O2
6Mg + Al3O2
3Mg + Al2O3 1 2 3 4 5

5. 4. One of the main assumptions of the kinetic molecular theory of gases is that the particles of an ideal gas--
Must be single atoms instead of molecules
Are in constant motion
Must be maintained at very high pressures
Must be highly chemically reactive 1 2 3 4 5

6. Which is the correct formula for iron(III) sulfate?
Fe3(S04)2
FeSO4
Fe2(SO4)3
Fe2(SO3)3 1 2 3 4 5

7. 6. Which of these represents the empirical formula and the molecular formula, respectively, for a given organic compound?
CH and C2H2
CH and CH4
CH2 and C2H2
CH3 and C3H12 1 2 3 4 5

8. Specific Heat Capacities of Some Common Substances What probably causes water to have the highest specific heat of the substances listed above?
Molecule size
Molecular mass
Strong hydrogen bonds
High density of ice
Substance
Specific Heat Capacity (cal/g * °C)
Aluminum
0.21
Alcohol
0.58
Water
1.00
Wood
0.42 1 2 3 4 5

9. 8. Each beaker shown above contains 2
8. Each beaker shown above contains 2.2 grams of iron and 1 liter of 3M H2SO4 at STP. Which reaction will go to completion first and why?
Beaker A because of increased surface area
Beaker B because of increased surface area
Beaker A because of a higher concentration level
Beaker B because of a higher concentration level. 1 2 3 4 5

10. The element chlorine exists as two naturally occurring isotopes
The element chlorine exists as two naturally occurring isotopes. Cl-35 occurs 75% of the time and Cl-37 occurs 25% of the time. Which of the following calculations should be used to calculate the correct average atomic mass of chlorine? A B C D 1 2 3 4 5

11. 10. The average kinetic energy of a sample of water molecules is__
Increased as the temperature is decreased.
Increased as the temperature is increased
Unaffected by temperature changes
Always equal to zero 1 2 3 4 5

12. 11. Electronegativity differences are often helpful in determining the bond character between two atoms. A general rule states t hat if the electronegativity difference between two atoms is greater than 1.67, an ionic bond would most likely be formed. Using the chart above, which pair of atoms would probably form the strongest ionic bond?
Al-P
Na-Cl
K-F
Ca-O 1 2 3 4 5

13. 12. The mass of an object was recorded as 9. 93g, 9. 90g, and 10
12. The mass of an object was recorded as 9.93g, 9.90g, and using an electronic analytical balance. What is the average of these three masses expressed to the correct number of significant figures?
9.9g
9.95g
10.0g
10.00g 1 2 3 4 5

14. 13. Radioactive iodine-131 has a half-life of eight days
13. Radioactive iodine-131 has a half-life of eight days. The amount of a gram sample left after 32 days would be---
6.25g
12.5g
25.0g
50.0g 1 2 3 4 5

15. 2H2S(g) + 3O2(g)→2H2O(g) + 2SO2(g) If 3
2H2S(g) + 3O2(g)→2H2O(g) + 2SO2(g) If 3.50 g of H2S are used in the above reaction, what will be the theoretical yield of water in grams?
0.102 g
0.185 g
1.85 g
185 g 1 2 3 4 5

16. 15.Which of these describes a tendency for atomic radii as displayed on the periodic chart?
Atomic radii decrease left to right across a period.
Atomic radii increase left to right across a period.
Atomic radii decrease top to bottom down a group.
Atomic radii increase, then decrease from top to bottom down a group. 1 2 3 4 5

17. 16. A student conducted an experiment and was interested in the mass of the product of the chemical reaction. What is the mass of the NaCl? NaHCO3(s) + HCl(aq)→NaCl(aq) + CO2(g) + H2O (g)
0.75g
1.75g
2.25g
2.50g

18. 17. A solution contains 225g of glucose, C6H12O6 dissolved in enough water to make 0.825L of solution. What is the molarity of the solution?
0.66 M
0.97 M
1.03 M
1.52 M 1 2 3 4 5

19. The water was not completely evaporated from the compound.
18. A student wanted to calculate the formula for hydrated copper sulfate. After careful massing, she heated the compound to remove the water. She calculated the formula to be CuSo4.4H2O. The actual formula was CuSO4.5H2O. What is the most likely source of analytical error in the student’s experiment?
The water was not completely evaporated from the compound.
The actual mass of the anhydrous CuSo4 was less than the measurement.
The CuSO4 reacted with elemental copper.
The atmospheric pressure prevented complete reaction. 1 2 3 4 5

20. 19. What is the percentage of aluminum in aluminum oxide (Al2O3)?
47%
48%
53%
54% 1 2 3 4 5

21. 20. Which of these conclusions can be drawn from Rutherford’s experiment?
Each atom contains electrons.
The nucleus of an atom can be split.
Each atom contains protons.
Atoms are mostly empty space. 1 2 3 4 5

22. It has a different number of protons and two less neutrons than C-12.
How does the radioactive isotope C-14 differ from its stable counterpart C-12?
It has a different number of protons and two less neutrons than C-12.
It has the same number of protons and two more electrons than C-12.
It has the same number of protons but tow more neutrons than C-12.
It has a different number of protons and two more neutrons than C-12. 1 2 3 4 5

23. 22. A compound has 50% sulfur and 50% oxygen
22. A compound has 50% sulfur and 50% oxygen. What is its empirical formula?
SO4
S2O4
SO3
SO2 1 2 3 4 5

24. 23. An experiment yielded that above temperature and time information
23. An experiment yielded that above temperature and time information. What is the freezing point of the material in this experiment if the material is a solid at time zero?
-25°C
0°C
25°C
50°C 1 2 3 4 5

25. 24. How many milliliters of 2. 00 M H2SO4 are needed to provide 0
24. How many milliliters of 2.00 M H2SO4 are needed to provide mole of H2SO4?
125 mL
1.25 X 101 mL
8.00 X 103 mL
8.00 mL 1 2 3 4 5

26. 25. A(s) + B(s)→D(g) + heat The reaction shown above is ___
An endothermic reaction
An exothermic reaction
A decomposition reaction
A double-replacement reaction 1 2 3 4 5

27. Chlorine forms a 1- ion. How many electrons does a chloride ion have?16 17 18 1 2 3 4 5

28. 27. According to the data, which of the following represents the average density for sample X using the correct number of significant figures?
1 g/mL
0.8 g/mL
0.81 g/mL
0.821 g/mL 1 2 3 4 5

29. CH4 + 2O2→ CO2 + 2H2O The number of grams of oxygen required for the complete combustion of 4.00 grams of methane (CH4) is ___
4.00g
8.00g
16.0g
32.0g 1 2 3 4 5

30. 29. Which of the groups below has the electron dot structure shown?
Noble gases
Halogens
Alkali metals
Transition elements 1 2 3 4 5

31. Slowly pour the 5 M acid into water
30. A student must make a 3 M acid solution using a 5 M acid solution. Which of these is the safest way to make the solution?
Slowly pour the 5 M acid into water
Slowly add water to the 5 M acid solution
Mix half the acid with water, then add the remaining water
Mix half the water with the acid, then add the remaining acid 1 2 3 4 5

32. 31. Four aqueous solutions and their concentrations are shown in the illustration. Which of the solutions is most likely to be the strongest conductor of electricity? I II
III IV 1 2 3 4 5

33. Decreasing the air pressure Increasing the air pressure
32. Water can be made to boil above its normal boiling point of 100°C by ___
Decreasing the air pressure
Increasing the air pressure
Increasing the heat being applied
Decreasing the volume of the container 1 2 3 4 5

34. Flush the affected area with water Apply a neutralizing agent
33. What is the first step that should be taken when a caustic chemical gets into a person’s eye?
Identify the chemical
Call for an ambulance
Flush the affected area with water
Apply a neutralizing agent 1 2 3 4 5

35. 34. According to the table, which of these probably has the strongest bonds?
Hydrogen gas
Iron crystals
Sodium chloride
Water 1 2 3 4 5

36. Decrease the concentration of SO2 Decrease the concentration of O2
35. In the reaction 2SO2 (g) + O2 (g)↔2SO3 (g), which change would cause the greatest increase in the concentration of SO3?
Decrease the concentration of SO2
Decrease the concentration of O2
Increase the concentration of SO2
Increase the concentration of O2 1 2 3 4 5

37. 36. A catalyst accelerates a chemical reaction because the___
Catalyst decreases the number of collisions in a reaction
Activation energy of the reaction is lowered in the presence of a catalyst
Catalyst decreases the concentration of the reactants
Temperature of the reaction increases due to the catalyst 1 2 3 4 5

38. 37. A compound is composed of 58. 8% C, 9. 8% H, and 31
37. A compound is composed of 58.8% C, 9.8% H, and 31.4 % O, and the molar mass is 102 g/mol. What is the molecular formula for this compound?
C2H10O3
C5H5O3
C5H10O2
CH3O3 1 2 3 4 5

39. Which of these shows a volume of 1.25 liters expressed in milliliters?
125 mL
12.5 X 101 mL
1.25 X 102 mL
1.25 X 103 mL 1 2 3 4 5

40. 39. An element has an electron configuration of 1s22s22p63s2
39. An element has an electron configuration of 1s22s22p63s2. Which of these will be in the same group as this element?
1s22s22p6
1s22s22p63s23p64s2
1s22s22p63p1
1s22s22p63s23p6 1 2 3 4 5

41. 40. Very Active Metal + Water→Metal Hydroxide + ?
Oxygen
Hydrogen
Metal oxide
Air 1 2 3 4 5

42. 41. Which of these elements is the most chemically active?Cl Br I 1 2 3 4 5

43. 42. If the heat of fusion of water is 3
42. If the heat of fusion of water is 3.4 X 102 J/g, the amount of heat energy required to change 15.0 grams of ice at 0°C to 15.0 grams of water at 0°C is ___
3.4 X 102 J
2.4 X 103 J
5.1 X 103 J
1.0 X 104 J 1 2 3 4 5

44. Decreases by one-fourth Is doubled Is halved
43. If the pressure exerted on a confined gas is doubled, then the volume of the gas__
Increases four times
Decreases by one-fourth
Is doubled
Is halved 1 2 3 4 5

45. Activation energy increases Energy of the products increases
44. If the temperature of a reaction is increased, the reaction proceeds at a much quicker rate because the___
Activation energy increases
Energy of the products increases
Frequency of collisions between reactants increases
Energy of the activated complex increases 1 2 3 4 5

46. 45. The formula H2SO4 is representative of which of the following?
A catalyst
A base
An acid
An organic compound 1 2 3 4 5

47. 46. Which compound contains both ionic and covalent bonds?
NH4Cl
MgBr2
CH4
NH3 1 2 3 4 5

48. Which volume will be occupied by a gas containing 6
Which volume will be occupied by a gas containing 6.02 X 1023 atoms at STP?
1.0 L
11.2 L
22.4 L
44.8 L 1 2 3 4 5

49. 48. Using the chart, which of these combinations will probably form a precipitate?
Ammonium chloride
Barium bromide
Calcium chromate
Copper (II) carbonate 1 2 3 4 5

50. 49. A sample of oxygen gas is collected over water at 22°C and 98
49. A sample of oxygen gas is collected over water at 22°C and kPa pressure. If the partial pressure of the water is 2.67 kPa, the partial pressure of the oxygen is___
93.33 kPa
96.00 kPa
98.66 kPa
kPa 1 2 3 4 5

51. 50. The hydrogen ion concentration is 1 X 10-7
50. The hydrogen ion concentration is 1 X What is the pH of this solution? 1 7 10 14 1 2 3 4 5