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Chapter 1. Measurement
1. The SI unit of time is the
A. hour
B. second
C. minute
D. ampere
2. The diameter of an atom is approximately 1 10-7 mm. What is this diameter when expressed in nanometers?
A. 1 10-18 nm
B. 1 10-15 nm
C. 1 10-9 nm
D. 1 10-1 nm
3. 6.0 km is how many micrometers?
A. 6.0 106 µm
B. 1.7 10-7 µm
C. 6.0 109 µm
D. 1.7 10-4 µm
4. The SI prefixes giga and micro represent, respectively:
A. 10-9 and 10-6.
B. 106 and 10-3.
C. 103 and 10-3.
D. 109 and 10-6.
5. Which of these quantities represents the largest mass?
A. 2.0 102 mg
B. 0.0010 kg
C. 1.0 105 g
D. 2.0 102 cg
6. How many cubic centimeters are there in exactly one cubic meter?
A. 1 10-6 cm3
B. 1 10-3 cm3
C. 1 10-2 cm3
D. 1 106 cm3
7. Ammonia boils at -33.4C. What temperature is this in F?
A. -60.1F
B. -92.1F
C. -28.1F
D. +13.5F
Chapter 1 key:
1. B
2. D
3. C
4. D
5. D
6. D
7. C
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Chapter 2 Atoms Molecules and Ions
__________________________________________________ _________________________
NOTE: A periodic table is required to work many of the problems in this chapter.
1. Which of these elements is most likely to be a good conductor of electricity?
A. N
B. S
C. He
D. Cl
E. Fe
2. An atom of the isotope sulfur-31 consists of how many protons, neutrons, and electrons?
(p = proton, n = neutron, e = electron)
A. 15 p, 16 n, 15 e
B. 16 p, 15 n, 16 e
C. 16 p, 31 n, 16 e
D. 32 p, 31 n, 32 e
E. 16 p, 16 n, 15 e
3. A magnesium ion, Mg2+, has
A. 12 protons and 13 electrons.
B. 24 protons and 26 electrons.
C. 12 protons and 10 electrons.
D. 24 protons and 22 electrons.
E. 12 protons and 14 electrons.
4. Which of these pairs of elements would be most likely to form an ionic compound?
A. P and Br
B. Cu and K
C. C and O
D. O and Zn
E. Al and Rb
5. What is the formula for the ionic compound formed by calcium ions and nitrate ions?
A. Ca3N2
B. Ca(NO3)2
C. Ca2NO3
D. Ca2NO2
E. CaNO3
6. Which is the correct formula for copper(II) phosphate?
A. Cu2PO4
B. Cu3(PO4)2
C. Cu2PO3
D. Cu(PO4)2
E. Cu(PO3)2
7. The correct name for NH4NO3 is
A. ammonium nitrate.
B. ammonium nitrogen trioxide.
C. ammonia nitrogen oxide.
D. hydrogen nitrogen oxide.
E. hydrogen nitrate.
8. The chemical name for ClO3- is "chlorate ion". Therefore, the name of HClO3 is
A. hydrochloric acid.
B. chloroform.
C. hydrogen trioxychloride.
D. chlorous acid.
E. chloric acid.
9. The Stock system name for As2S5 is
A. arsenic(V) sulfide.
B. diarsenic pentasulfide.
C. arsenic(III) sulfide.
D. arsenic(V) sulfate.
E. diarsenic sulfate.
10. Which of these elements is chemically similar to oxygen?
A. sulfur
B. calcium
C. iron
D. nickel
E. sodium
Chapter 2 Key
1. E
2. B
3. C
4. D
5. B
6. B
7. A
8. E
9. B
10.A
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Chapter 3 Mass Relationships in Chemical Reactions
__________________________________________________ _________________________
1. What is the mass, in grams, of one copper atom?
A. 1.055 10-22 g
B. 63.55 g
C. 1 amu
D. 1.66 10-24 g
E. 9.476 1021 g
2. Determine the number of moles of aluminum in 96.7 g of Al.
A. 0.279 mol
B. 3.58 mol
C. 7.43 mol
D. 4.21 mol
E. 6.02 1023 mol
3. Which of the following samples contains the greatest number of atoms?
A. 100 g of Pb
B. 2.0 mole of Ar
C. 0.1 mole of Fe
D. 5 g of He
E. 20 million O2 molecules
4. Formaldehyde has the formula CH2O. How many molecules are there in 0.11 g of formaldehyde?
A. 6.1 10-27
B. 3.7 10-3
C. 4
D. 2.2 1021
E. 6.6 1022
5. How many sulfur atoms are present in 25.6 g of Al2(S2O3)3?
A. 0.393
B. 6
C. 3.95 1022
D. 7.90 1022
E. 2.37 1023
6. The percent composition by mass of a compound is 76.0% C, 12.8% H, and 11.2% O. The molar mass of this compound is 284.5 g/mol. What is the molecular formula of the compound?
A. C10H6O
B. C9H18O
C. C16H28O4
D. C20H12O2
E. C18H36O2
7. What is the coefficient of H2O when the following equation is properly balanced with the smallest set of whole numbers?
___ Al4C3 + ___ H2O ___ Al(OH)3 + ___ CH4
A. 3
B. 4
C. 6
D. 12
E. 24
8. When 22.0 g NaCl and 21.0 g H2SO4 are mixed and react according to the equation below, which is the limiting reagent?
2NaCl + H2SO4 Na2SO4 + 2HCl
A. NaCl
B. H2SO4
C. Na2SO4
D. HCl
E. No reagent is limiting.
9. Hydrochloric acid can be prepared by the following reaction:
2NaCl(s) + H2SO4(aq) 2HCl(g) + Na2SO4(s)
How many grams of HCl can be prepared from 2.00 mol H2SO4 and 150 g NaCl?
A. 7.30 g
B. 93.5 g
C. 146 g
D. 150 g
E. 196 g
10. What is the theoretical yield of chromium that can be produced by the reaction of 40.0 g of Cr2O3 with 8.00 g of aluminum according to the chemical equation below?
2Al + Cr2O3 Al2O3 + 2Cr
A. 7.7 g
B. 15.4 g
C. 27.3 g
D. 30.8 g
E. 49.9 g
Chapter 3 Key
1. A
2. B
3. B
4. D
5. E
6. E
7. D
8. A
9. B
10. B
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Chapter 4 Reactions in Aqueous Solution
__________________________________________________ _________________________
1. What mass of K2CO3 is needed to prepare 200. mL of a solution having a potassium ion concentration of 0.150 M?
A. 4.15 g
B. 10.4 g
C. 13.8 g
D. 2.07 g
E. 1.49 g
2. A 50.0 mL sample of 0.436 M NH4NO3 is diluted with water to a total volume of 250.0 mL. What is the ammonium nitrate concentration in the resulting solution?
A. 21.8 M
B. 0.459 M
C. 2.18 10-2 M
D. 8.72 10-2 M
E. 0.109 M
3. How many milliliters would you need to prepare 60.0 mL of 0.200 M HNO3 from a stock solution of 4.00 M HNO3?
1. 3 mL
2. 240 mL
3. 24 mL
4. 1000 mL
5. 60 mL
4. What volume, in mL, of a 3.89 x 10-2 M solution is required to provide 2.12 g of KBr?
(Atomic weights: K = 39.10, Br = 79.90).
a) 520
b) 458
c) 389
d) 325
e) 425
Chapter 4 Key:
1. A
2. D
3. A
4. B
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Chapter 5 Gases
__________________________________________________ _________________________
1. Which of the following is/are characteristic(s) of gases?
A. High compressibility
B. Relatively large distances between molecules
C. Formation of homogeneous mixtures regardless of the nature of gases
D. High compressibility AND relatively large distances between molecules
E. High compressibility, relatively large distances between molecules AND formation of homogeneous mixtures regardless of the nature of gases
2. A small bubble rises from the bottom of a lake, where the temperature and pressure are 4C and 3.0 atm, to the water's surface, where the temperature is 25C and the pressure is 0.95 atm. Calculate the final volume of the bubble if its initial volume was 2.1 mL.
A. 0.72 mL
B. 6.2 mL
C. 41.4 mL
D. 22.4 mL
E. 7.1 mL
3. Calculate the mass, in grams, of 2.74 L of CO gas measured at 33C and 945 mmHg.
A. 0.263 g
B. 2.46 g
C. 3.80 g
D. 35.2 g
E. 206 g
4. Which of the following gases will have the greatest density at the same specified temperature and pressure?
A. H2
B. CClF3
C. CO2
D. C2H6
E. CF4
5. Determine the molar mass of chloroform gas if a sample weighing 0.389 g is collected in a flask with a volume of 102 cm3 at 97C. The pressure of the chloroform is 728 mmHg.
A. 187 g/mol
B. 121 g/mol
C. 112 g/mol
D. 31.6 g/mol
E. 8.28 10-3 g/mol
6. What is the molar mass of Freon-11 gas if its density is 6.13 g/L at STP?
A. 0.274 g/mol
B. 3.64 g/mol
C. 78.2 g/mol
D. 137 g/mol
E. 365 g/mol
7. A mixture of three gases has a total pressure of 1,380 mmHg at 298 K. The mixture is analyzed and is found to contain 1.27 mol CO2, 3.04 mol CO, and 1.50 mol Ar. What is the partial pressure of Ar?
A. 0.258 atm
B. 301 mmHg
C. 356 mmHg
D. 5,345 mmHg
E. 8,020 mmHg
8. A sample of hydrogen gas was collected over water at 21C and 685 mmHg. The volume of the container was 7.80 L. Calculate the mass of H2(g) collected. (Vapor pressure of water = 18.6 mmHg at 21C.)
A. 0.283 g
B. 0.572 g
C. 0.589 g
D. 7.14 g
E. 435 g
9. A 0.271 g sample of an unknown vapor occupies 294 mL at 140C and 847 mmHg. The empirical formula of the compound is CH2. What is the molecular formula of the compound?
A. CH2
B. C2H4
C. C3H6
D. C4H8
E. C6H12
10. How many liters of chlorine gas at 25C and 0.950 atm can be produced by the reaction of 12.0 g of MnO2?
MnO2(s) + 4HCl(aq) MnCl2(aq) + 2H2O(l) + Cl2(g)
A. 5.36 10-3 L
B. 0.138 L
C. 0.282 L
D. 3.09 L
E. 3.55 L
Chapter 5 Key
1. E
2. E
3. C
4. B
5. B
6. D
7. C
8. B
9. B
10. E
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