Download 2014 Q1—Mid Quarter Exam Chapter 9—Stoichiometry 1. The

2014 Q1—Mid Quarter Exam
Chapter 9—Stoichiometry
1. The coefficients in a chemical equation represent the
a. masses, in grams, of all reactants and products.
b. relative numbers of moles of reactants and products.
c. number of atoms in each compound in a reaction.
d. number of valence electrons involved in the reaction.
2. In the reaction N2 + 3H2  2NH3, what is the mole ratio of nitrogen to ammonia?
a. 1:1
c. 1:3
b. 1:2
d. 2:3
3. In the reaction Zn + H2SO4  ZnSO4 + H2, what is the mole ratio of zinc to sulfuric acid?
a. 1:6
c. 1:2
b. 1:1
d. 3:1
4. In the equation 2KClO3  2KCl + 3O2, how many moles of oxygen are produced when 3.0 mol of
KClO3 decompose completely?
a. 1.0 mol
c. 3.0 mol
b. 2.5 mol
d. 4.5 mol
5. For the reaction 2H2 + O2 2H2O, how many moles of water can be produced from 6.0 mol of
oxygen?
a. 2.0 mol
c. 12 mol
b. 6.0 mol
d. 18 mol
Chapter 8—Chemical Equations and Reactions
6. A solid produced by a chemical reaction in solution that separates from the solution is called
a. a precipitate.
c. a molecule.
b. a reactant.
d. the mass of the product.
7. In writing an equation that produces hydrogen gas, the correct representation of hydrogen gas is
a. H.
c. H2.
b. 2H.
d. OH.
8. To balance a chemical equation, it may be necessary to adjust the
a. coefficients.
c. formulas of the products.
b. subscripts.
d. number of products.
9. A chemical equation is balanced when the
a. coefficients of the reactants equal the coefficients of the products.
b. same number of each kind of atom appears in the reactants and in the products.
c. products and reactants are the same chemicals.
d. subscripts of the reactants equal the subscripts of the products.
10. Which coefficients correctly balance the formula equation NH4NO2(s) N2(g) + H2O(l)?
a. 1, 2, 2
c. 2, 1, 1
b. 1, 1, 2
d. 2, 2, 2
11. The reaction 2Mg(s) + O2(g)  2MgO(s) is a
a. synthesis reaction.
c. single-replacement reaction.
b. decomposition reaction.
d. double-replacement reaction.
12. The reaction 2HgO(s)  2Hg(l) + O2(g) is a(n)
a. single-replacement reaction.
c. ionic reaction.
b. synthesis reaction.
d. decomposition reaction.
13. The reaction 2KClO3(s)  2KCl(s) + 3O2(g) is a(n)
a. synthesis reaction.
c. combustion reaction.
b. decomposition reaction.
d. ionic reaction.
14. In the equation 2Al(s) + 3Fe(NO3)2(aq)  3Fe(s) + 2Al(NO3)3(aq), iron has been replaced by
a. nitrate.
c. aluminum.
b. water.
d. nitrogen.
15. What is the balanced equation when aluminum reacts with copper(II) sulfate?
a. Al + Cu2S  Al2S + Cu
c. Al + CuSO4  AlSO4 + Cu
b. 2Al + 3CuSO4  Al2(SO4)3 + 3Cu
d. 2Al + Cu2SO4  Al2SO4 + 2Cu
16. Magnesium bromide + chlorine yield
a. Mg and BrCl.
b. MgCl and Br2.
c. MgBrCl.
d. Mg(Cl)2 and Br2.
Chapter 7—Chemical Formulas and Chemical Compounds
17. What is the formula for aluminum sulfate?
a. AlSO4
c. Al2(SO4)3
b. Al2SO4
d. Al(SO4)3
18. What is the formula for barium hydroxide?
a. BaOH
c. Ba(OH)2
b. BaOH2
d. Ba(OH)
19. Name the compound Zn3(PO4)2.
a. zinc potassium oxide
b. trizinc polyoxide
c. zinc phosphate
d. zinc phosphite
20. Name the compound CuCO3.
a. copper(I) carbonate
b. cupric trioxycarbide
c. cuprous carbide
d. copper(II) carbonate
21. What is the formula for nitrogen trifluoride?
a. NiF3
c. N3F
b. NF3
d. Ni3F
22. What is the formula for sulfur dichloride?
a. NaCl2
b. SCl2
c. S2Cl
d. S2Cl2
23.The molar mass of MgI2 is
a. the sum of the masses of 1 mol of Mg and 2 mol of I.
b. the sum of the masses of 1 mol of Mg and 1 mol of I.
c. the sum of the masses of 2 mol of Mg and 2 mol of I.
d. impossible to calculate.
24. The molar mass of NH3 is 17.03 g/mol. How many moles of NH3 are present in 107.1 g?
a. 0.1623 mol
c. 6.289 mol
b. 3.614 mol
d. 107.1 mol
25. How many Mg2+ ions are found in 1.00 mol of MgO?
a. 3.01  1023
c. 12.04  1023
23
b. 6.02  10
d. 6.02  1025
Chapter 5—The Periodic Law
26. The periodic table
a. permits the properties of an element to be predicted before the element is discovered.
b. will be completed with element 118.
c. has been of little use to chemists since the early 1900s.
d. was completed with the discovery of the noble gases.
27. What are the elements with atomic numbers from 58 to 71 in the periodic table called?
a. the lanthanide elements
c. the actinide elements
b. the noble gases
d. the alkali metals
28. In the modern periodic table, elements are ordered according to
a. decreasing atomic mass.
c. increasing atomic number.
b. Mendeleev's original design.
d. the date of their discovery.
29. Elements in a group or column in the periodic table can be expected to have similar
a. atomic masses.
c. numbers of neutrons.
b. atomic numbers.
d. properties.
Chapter 3—Atoms: The Building Blocks of Matter
30. If 63.5 g of copper (Cu) combine with 16 g of oxygen (O) to form the compound CuO, how many
grams of oxygen will be needed to combine with the same amount of copper to form the compound
CuO2?
a. 16 g
c. 64 g
b. 32 g
d. 127 g
31. Dalton's atomic theory helped to explain the law of conservation of mass because it stated that
atoms
a. could not combine.
c. all had the same mass.
b. could not be created or destroyed.
d. were invisible.
32. The mass of a neutron is
a. about the same as that of a proton.
b. about the same as that of an electron.
c. double that of a proton.
d. double that of an electron.
33. Most of the volume of an atom is occupied by the
a. nucleus.
c. electron cloud.
b. nuclides.
d. protons.
34. The smallest unit of an element that can exist either alone or in combination with other such
particles of the same or different elements is the
a. electron.
c. neutron.
b. proton.
d. atom.
35. Atoms of the same element that have different masses are called
a. moles.
c. nuclides.
b. isotopes.
d. neutrons.
36. Helium-4 and helium-3 are
a. isotopes.
b. different elements.
c. compounds.
d. nuclei.
37. All atoms of the same element have the same
a. atomic mass.
c. mass number.
b. number of neutrons.
d. atomic number.
38. An aluminum isotope consists of 13 protons, 13 electrons, and 14 neutrons. Its mass number is
a. 13.
c. 27.
b. 14.
d. 40.
39. In the figure above, a neutral atom of silicon contains
a. 14 electrons.
c. 16 electrons.
b. 28.09 electrons.
d. 38 electrons.
40. Nickel-60 (atomic number 28) has
a. 28 neutrons.
b. 32 neutrons.
c. 60 neutrons.
d. 88 neutrons.
41. An electrically neutral atom of mercury (atomic number 80) has
a. 80 neutrons and 80 electrons.
c. 80 protons and 80 neutrons.
b. 40 protons and 40 electrons.
d. 80 protons and 80 electrons.
42. The number of atoms in a mole of any pure substance is called
a. its atomic number.
c. its mass number.
b. Avogadro's constant.
d. its gram-atomic number.
43. The atomic number of neon is 10. The atomic number of calcium is 20. Compared with a mole of
neon, a mole of calcium contains
a. twice as many atoms.
c. an equal number of atoms.
b. half as many atoms.
d. 20 times as many atoms.
44. If samples of two different elements each represent one mole, then
a. they are equal in mass.
c. their molar masses are equal.
b. they contain the same number of atoms.
d. they have the same atomic mass.
45. The mass of 1 mol of chromium (atomic mass 51.996 amu) is
a. 12 g.
c. 51.996 g.
b. 198 g.
d. 6.02  1023 g.
46. A quantity of sodium (atomic mass 22.99 amu) contains 6.02  1023 atoms. The mass of the sodium
is
a. 6.02  1023 g.
c. 22.99 g.
b. 3.88 g.
d. not determinable.
47. The mass of exactly 5 mol of cesium (atomic mass 132.9 amu) is
a. 664.5 g.
c. 6.02  1023 g.
b. 132.9 g.
d. 5 g.
Chapter 2—Measurements and Calculations
48. Which of the following observations is qualitative?
a. A chemical reaction is complete in 2.3 seconds.
b. The solid has a mass of 23.4 grams.
c. The pH of a liquid is 5.
d. Salt deposits form from an evaporated liquid.
49. A theory is best described as a
a. series of experimental observations.
b. generalization that explains a body of known facts or phenomena.
c. scientifically proven fact.
d. testable statement.
50. The SI standard units for length and mass are
a. centimeter and gram.
c. centimeter and kilogram.
b. meter and gram.
d. meter and kilogram.
51. The symbol mm represents
a. micrometer.
b. millimeter.
c. milliliter.
d. meter.
52. The most appropriate SI unit for measuring the length of an automobile is the
a. centimeter.
c. meter.
b. kilometer.
d. liter.
53. The density of pure diamond is 3.5 g/cm3. The mass of a diamond is 0.25 g. Find its volume.
a. 0.071 cm3
c. 3.5 cm3
3
b. 0.875 cm
d. 14 cm3
54. 0.05 cm is the same as
a. 0.000 05 m.
b. 0.005 mm.
c. 0.05 m.
d. 0.5 mm.
55. The number of grams equal to 0.5 kg is
a. 0.0005.
b. 0.005.
c. 500.
d. 5000.
56. A measurement is said to have good precision if it
a. agrees closely with an accepted standard.
b. agrees closely with other measurements of the same quantity.
c. has a small number of significant figures.
d. has a large number of significant figures.
57. The measurement 0.020 L is the same as
a. 2.0  10–3 L.
b. 2.0  102 L.
c. 2.0  10–2 L.
d. 2.0  10–1 L.
58. When 6.02  1023 is multiplied by 9.1  10–31, the product is
a. 5.5  10–8.
c. 5.5  10–7.
54
b. 5.5  10 .
d. 5.5  10–53.
59. The capacity of a Florence flask is 250 mL. Its capacity in liters expressed in scientific notation is
a. 2.5  10–2 L.
c. 2.5  101 L.
–1
b. 2.5  10 L.
d. 2.5  102 L.
Chapter 1—Matter and Change
60. A physical property may be investigated by
a. melting ice.
c. allowing silver to tarnish.
b. letting milk turn sour.
d. burning wood.
61. An example of a chemical change is
a. sanding wood.
b. melting ice.
c. milk going sour.
d. vaporizing gasoline.
62. The particles in a solid are
a. packed closely together.
b. very far apart.
c. constantly in motion.
d. able to slide past each other.
63. The state of matter in which a material has a definite volume but no definite shape is the
a. gaseous state.
c. frozen state.
b. solid state.
d. liquid state.
64. The homogeneous mixture in the illustration above is in container
a. a.
c. c.
b. b.
d. d.
65. Which part of the illustration above shows the particles in a heterogeneous mixture?
a. a
c. c
b. b
d. d
66. Based on their location in the figure above, oxygen and selenium have
a. the same number of neutrons.
c. similar properties.
b. the same conductivity.
d. the same number of electron orbitals.
67. Based on its location in the figure above, you could infer that ____ is very unreactive.
a. Ca
c. Si
b. P
d. Ar
68. Elements in a group in the periodic table can be expected to have similar
a. atomic masses.
c. numbers of neutrons.
b. atomic numbers.
d. properties.
69. The elements that border the zigzag line in the periodic table are
a. inactive.
c. metalloids.
b. metals.
d. nonmetals.