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Chemistry
Final Review
1. The number .003050 contains how many significant figures?
A. 3 B. 4 C. 6 D. 5 E. 2
2. How many seconds are in six months? (assume 30 days per month)
A. 15552000 B. 648000 C. 518400
3. Which particle has no charge?
A. Proton B. Electron C. Neutron D. Alpha E. None of the above
4. Which is the correct arrangement of particles from heaviest to lightest?
A. Neutron, proton, electron B. Proton, neutron, electron C. Electron, neutron, proton D. Electron,
proton, neutron
5. Most of the mass of an atom is in the ____and most of the volume is in the ___.
A. electron cloud, nucleus B. nucleus, electron cloud C. protons, electrons D. electrons, protons
6. Atoms with the same number of neutrons and a different number of protons are
A. isotopes B. ions C. different elements
7. If two atoms have the same chemical properties but different masses they are
A. ions B. different elements C. isotopes
8. Atoms with the same number of protons and a different number of electrons are
A. ions B. different elements C. isotopes
9. If Mg and N form a compound the formula will be
A. Mg2N3 B. Mg3N2 C. MgN D. MgN2 E. Mg2N
10. If Al forms an ion its charge will be
A. 2 B. 3 C. 1 D. -3 E. -2
11. If 238U undergoes alpha decay the resulting nucleus is
A. 234Th B. 234Ra C. 236Ra D. 236Th E. None of the above
12. Is 14C undergoes beta decay the resulting nucleus is
A. 14N B. 13C C. 13N D. 14B E. 13B
13. Which type of radiation will penetrate the farthest through matter?
A. Alpha B. Gamma C. Beta D. Infrared E. Visible
14. Complete the following nuclear equation: 9Be + 4He = 1n + ___
A. 13C B. 12C C. 13Al D. 13B E. None of the above
15. Which species has more electrons?
A. Oxide ion B. Neon C. Fluoride ion D. Sodium ion E. Nitrate ion
16. Which is an ionic compound?
A. BCl3 B. CuSn C. AlCl3 D. N
17. In a balanced chemical equation there are:
A. Equal numbers of each type of atom on both sides of the equation
B. Equal numbers of molecules on each side of the equation
C. A and B
D. Neither A nor B
18. How many hydrogen are present here? (NH4)3PO4
A. 4 B. 8 C. 12 D. 24
Give chemical equations for this sentence:
What are the coefficients when the following chemical reactions are balanced?
19. C7H14O7 + O2 = CO2 + H2O
A. 1,7,7,7 B. 2,10,10,10 C. 1,4,5,4 D. 1,5,4,5
20. CH4 + NH3 + O2 = HCN + H2O
A. 2,2,3,2,6 B. 1,1,2,1,3 C. 1,1,3,1,2 D. 1,1,3,1,3 E. Can’t be balanced
21. NaCl + SO2 + H2O + O2 = HCl + Na2SO4
A. 2,1,2,1,2,1 B. 4,2,2,2,4,2 C. 4,2,2,1,4,2 D. 8,4,4,2,8,4 E. 8,4,4,4,8,2
22. The coefficients when this equation is balanced are:
Calcium oxide added to hydrobromic acid produces water and calcium bromide
A. 1,2,1,1 B. 2,1,2,1 C. 2,1,2,2 D. 2,4,2,2 E. 4,2,4,4
23. The coefficients when this equation is balanced are : CH6N2 + N2O4 = N2 + H2O + CO2
A. 4,5,9,12,4 B. 2,3,4,6,3 C. 4,6,8,12,3 D. 8,10,18,24,8 E. 4,6,4,8,4
24. A mole is _______ of an object.
A. 22.4L B. 6.02X1023 C. 6.02X1023g D. 6.02X1023L E. 22.4
25. One mole of gas occupies _____L at STP.
A. 22.4L B. 44.8L C. 273L D. 6.02X10 23L E. 22.4
26. Ti2(SO4)3
A. 376g B. 336g C. 96g D. 128g E. 384g
27. Ca3(PO4)2
A. 230g B. 87g C. 310g D. 215g E. 246g
28. 5X1026 particles to moles of particles.
A. 830 moles B. 83 moles C. 1.2X10 -3 moles D. 1.2X10-2 moles E. 12moles
29. 60L of gas to moles of gas.
A. 3.6X1025 moles B. .37 moles C. 1344 moles. D. 9.97X10 -23 moles E. 2.7 moles
30. 50g of C to moles of C
A. 2.2 moles B. .24 moles C. 600 moles D. 4.17 moles E. 8.3X10 -23 moles
31. What is the mass of 50L of oxygen gas?
A. 160g B. 35.7g C. 350g D. 71.4g E. 80g
32. How many molecules are in 100g of oxygen gas?
A. 3.125 B. 2.69X1024 C. 3.76X1024 D. 6.25 E. 1.88X1024
33. 60g of CO2 gas will occupy how many liters at STP?
A. 48L B. 118L C. 91.5L D. 30.5L E. 75L
34. How many atoms are in 50g of phosphorus?
A. Can’t be determined B. 1.3X1024 C. 3.01X1025 D. 9.7X1023
35. Which is heavier 500L of Neon gas or 100L of krypton gas?
A. Ne B. Kr C. Neither D. Can’t be determined
36. Which takes up more space 10g of He or 300g of Xe?
A. Xe B. He C. Neither D. Can’t be determined
37. There are two unlabeled bottles in a lab. One is potassium chromate, (K 2CrO4) the other potassium
dichromate (K2Cr2O7). Analysis shows that one bottle contains 26.5% potassium. What is it?
A. Chromate B. Dichromate C. Can’t be determined D. A mixture of both
38. 150g of CH4 contains ___ grams of H.
A. 11.5g B. 112.5g C. 33.3g D. 37.5g E. 42.9g
39. What is the empirical formula of a compound that contains 65% O, 3.1% H and 31.6% P?
A. H3PO4 B. H3PO3 C. H5P2O8 D. H6P2O8 E. H6P2O7
40. What is the molecular formula of a compound that contains 87.5% N and 12.5% H? (mm=32g)
A. N2H5 B. NH2 C. NH3 D. N2H4 E. N3H5
41. Which has more O, 150g of Na2CO3 or 200g of K3PO4?
A. Na2CO3 B. K3PO4 C. Neither D. Can’t be determined
42-50 refer to the following chemical reaction shown by the skeletal equation: NH 3(g) + O2(g) = H2O(g) +
N2
42. How many moles of ammonia are required to make 5 moles of water?
A. 2.5 B. 3.3 C. 10 D. 20 E. 7.5
43. How many grams of oxygen are required to produce 20g of water? Assume excess ammonia.
A. 28.8g B. 35.56g C. 8.9g D. 1.1g E. 17.8g
44. How many liters of ammonia gas are required to react with 20L of oxygen gas?
A. 26.7L B. 20L C. 15L D. 32L E. 16L
45. How many molecules of NH3 are required to react with 20g of O2?
A. 1.5X1023 B. 5.0X1023 C. 7.2X023 D. 1.2 E. 5
46. How many grams of NH3 are required to react with 30L of oxygen gas?
A. 15.2 g B. 30.4g C. 60.8g D. 60 E. 15
47. How many grams of H2O can be produced from 20g O2 and 15g NH3?
A. 11.25g B. 27g C. 22.5g D. 33g E. 13.5g
48. What is the percent yield of water if stoichiometry predicts 10g will be produced and 3.5g are
recovered in a reaction?
A. .35% B. 35% C. 3.5% D. 28.6% E. 2.86%
49. What is the percent yield if 5g of water are recovered when 15g of H 2 are reacted with 20g of O2?
A. 5.5% B. .05% C. 22% D. 17.8% E. 8.9%
50. DELETED
51-56 refer to the following reaction shown by the skeletal equation H 3PO4 + Ca(OH)2 = H2O + Ca3(PO4)2
51. How many grams of water will be produced from 20g H 3PO4?
A. 44g B. 11g C. 22g D. 3.6g E. 1.2g
52. How many grams of calcium phosphate will be produced from 20g calcium hydroxide?
A. 28 B. 14g C. 56g D. 9.4g E. 84g
53. How many grams of water and calcium phosphate will be produced from 20g calcium hydroxide and
20g phosphoric acid?
A. 9.8g H2O and 28g Ca3(PO4)2 B. 11g H2O and 31.6g Ca3(PO4)2 C. 9.8g H2O and 31.6g Ca3(PO4)2 D. 11g H2O
and 28g Ca3(PO4)2
54. What is the percent yield when 20g of calcium phosphate is made from 50g H 3PO4 and excess calcium
hydroxide?
A. 50% B. 12.5% C. 25% D. 6.25% E. 75%
55. Which makes more water, 20g of H3PO4 or 30g Ca(OH)2?
A. Both make the same amount B. 30g calcium hydroxide C. 20g phosphoric acid
56. How many grams of Ca(OH)2 are required to react with 2.5g H3PO4?
A. 2.8g B. 1.26g C. 1.89g D. 1.4g E. 2.52g
57) How many decimeters are there in 15 centimeters?
a) 150 dm
b) 1.5 dm
c) 0.15 dm
d) none of these
58) How many kilograms are there in 4.21 pounds? There are 2.2 pounds in 1 kilogram.
a) 9.26 kg
b) 1.91 kg
c) 0.523 kg
d) none of these
59) An example of a chemical property is:
a) density
b) mass
c) acidity
d) solubility
60) What is the density of an object with a volume of 15 mL and a mass of 42 grams?
a) 0.352 g/mL
b) 2.80 g/mL
c) 630 g/mL
d) None of the above is correct.
61) Which of the following is not one of Dalton’s laws?
a) Atoms are indestructible.
b) Atoms of the same element have isotopes with different masses.
c) Atoms of different elements have different chemical and physical properties.
d) All of these are examples of Dalton’s laws.
62) The “plum pudding” model of the atom was devised by:
a) Dalton
b) Democritus
c) Rutherford
d) none of the above answers is correct
63) Bohr’s model of the atom was able to accurately explain:
a) Why spectral lines appear when atoms are heated.
b) The energies of the spectral lines for each element.
c) Why electrons travel in circular orbits around the nucleus.
d) none of the above answers is correct.
64) How many electrons does iron have?
a) 26
b) 30
c) 56
d) It depends on the isotope of iron
65) True or false: All isotopes are radioactive.
a) True
b) False
66) The colors of light given off when a sample is heated corresponds to:
a) The energy difference between the ground state and excited state of an element.
b) The amount of energy added to the sample.
c) The heat of the element.
d) None of the above
67) Orbitals hold:
a) A maximum of one electron each
b) A maximum of two electrons each
c) A number of electrons that depends on the energy level.
d) A number of electrons that depends on the type of orbital.
68) Which of the following elements has three valence electrons?
a) lithium
b) boron
c) nitrogen
d) more than one of the above
69) The electron configuration for gallium is:
a) [Ar] 4s24d104p1
b) [Ar] 4s23d103p1
c) [Ar] 4s23d104p1
d) none of these answers is correct.
70) Which element has the largest atomic radius?
a) fluorine
b) carbon
c) tin
d) iodine
71) Cations have:
a) Positive charge
b) Negative charge
c) No charge
d) It is impossible to predict the charge on a cation.
72) Which pair of atoms would most likely form an ionic compound when bonded to each
other?
a) calcium and fluorine
b) silicon and nitrogen
c) two oxygen atoms
d) none of the above would probably form an ionic compound
73) Which of the following is NOT a property of a salt?
a) They have ordered packing arrangements called “lattices”
b) They conduct electricity when dissolved in water or molten.
c) They have a low melting point but a high boiling point.
d) They are brittle.
74) The chemical name for Fe2O3 is:
a) iron oxide
b) iron (II) oxide
c) iron (III) oxide
d) iron (VI) oxide
75) The percent composition of aluminum in aluminum (III) hydroxide is:
a) 50%
b) 25%
c) 14%
d) 35%
76) Hydrates are defined as:
a) compounds with water molecules attached to them.
b) compounds that have had their water molecules removed
c) compounds that have been heated to high temperatures
d) none of these answers is correct.
77) Why do two nonmetals generally form covalent bonds with one another?
a) They have similar sizes
b) They have similar electronegativities
c) Nonmetals prefer to share electrons rather than transfer them
d) None of the above
78) Why do covalent compounds usually have lower melting and boiling points than ionic
compounds?
a) No bonds need to be broken to melt a covalent compound.
b) The intermolecular forces in ionic compounds are stronger than those in covalent
compounds.
c) Covalent molecules have higher electron affinities than ionic molecules.
d) None of the above is correct.
79) What is the total number of lone pairs in carbon disulfide?
a) two
b) four
c) eight
d) twelve
80) What is the shape of nitrogen trichloride?
a) trigonal planar
b) trigonal pyramidal
c) tetrahedral
d) none of these
81) VSEPR basically states that:
a) The repulsion of atomic nuclei help determine the shapes of covalent molecules.
b) The repulsion between electrons helps determine the shapes of covalent
molecules.
c) The repulsion between bonds helps determine the shapes of covalent molecules.
d) None of these statements is correct.
82) What is the molar mass of iron (III) hydroxide?
a) 73 grams/mol
b) 90 grams/mol
c) 107 grams/mol
d) none of these
83) How many grams are there in 2.1 moles of sodium?
a) 48.3 grams
b) 0.0913 grams
c) 11.0 grams
d) none of these is correct
84) How many molecules are there in 45 grams of aluminum trifluoride?
a) 2.28 x 1027 molecules
b) 3.23 x 1023 molecules
c) 1.12 x 1024 molecules
d) none of these is correct
85) The symbol (s) after a chemical compound lets you know that it is:
a) soluble in water
b) insoluble in water
c) a solid
d) more than one of the above
86) If we want to make 150 grams of ammonium sulfate by reacting ammonia with sulfuric acid,
how much ammonia will be needed?
a) 19.3 grams
b) 38.6 grams
c) 77.2 grams
d) none of these
87) How many grams of carbon dioxide will be formed when 100 grams of CH 4 is burned in
oxygen?
a) 122 grams
b) 244 grams
c) 488 grams
d) none of these
88) If the theoretical yield for a reaction was 156 grams and I actually made 122 grams of the
product, what is my percent yield?
a) 78.2%
b) 128%
c) 19.0%
d) none of these
89) Carbon disulfide undergoes a single displacement reaction with oxygen to form carbon
dioxide. If 100 grams of carbon disulfide are reacted with 50 grams of oxygen, what will
the limiting reagent be?
a) carbon disulfide
b) carbon dioxide
c) oxygen
d) sulfur
90) Hydrochloric acid reacts with calcium to form hydrogen and calcium chloride. If 100
grams of hydrochloric acid reacts with 100 grams of calcium, what is the limiting
reagent?
a) hydrochloric acid
b) hydrogen
c) calcium chloride
d) calcium
91) For the reaction in problem 90, how much of the nonlimiting reagent will be left over after
the reaction is complete?
a) 54.8 grams
b) 45.2 grams
c) 2.74 grams
d) none of these
92) Which are stronger, intramolecular forces or intermolecular forces?
a) Intramolecular forces
b) Intermolecular forces
93) Which compound is probably most polar of the following?
a) boron trichloride
b) oxygen difluoride
c) silicon tetrafluoride
d) selenium difluoride
94) Which of the following compounds is NOT polar?
a) ammonia
b) nitric acid
c) methane
d) none of these
95) The difference between dipole-dipole forces and hydrogen bonds are that:
a) dipole-dipole forces only exist between nonpolar molecules
b) dipole-dipole forces occur between polar molecules
c) dipole-dipole forces are caused by the interaction of partial charges on both
molecules.
d) None of the above are able to distinguish between dipole-dipole forces and
hydrogen bonds.
96) The electron sea theory is used to describe bonding in:
a) network atomic solids
b) ionic solids
c) molecular solids
d) metallic solids