Download HCCS Brown/LeMay/Bursten CHEM 1411: PRACETICE EXAM I

HCCS Brown/LeMay/Bursten CHEM 1411: PRACETICE EXAM I
Multiple Choices: Select ONE Best Answer. 40 questions
Chapter 1 (Q1 – Q13) , Chapter 2 (Q14 - Q26), Chapter 3 (Q27 – Q40 )
Page and sect provided are based on 13th edition.
1. A combination of table sugar, vinegar and water is an example of a ________.
A) homogeneous mixture
B) heterogeneous mixture
C) compound
D) pure substance
E) solid
p. 7 & p. 10. Know the definitions.
2. Which one of the following has the element name and symbol incorrectly matched?
A) P, potassium
B) Sn, tin
C) Fe, iron
D) Au, gold
E) Br, bromine
See Periodic Table (two pages inside the front cover). Know the atomic symbols.
3. Which of the following is a physical reaction?
A) color of carpet faded by sun light
B) dissolving zinc metal in acid producing hydrogen gas
C) burning a charcoal
D) fermentation of sugar
E) dry ice (solid carbon dioxide) becomes carbon dioxide gas
p. 12: Sect 1.3. Know the definitions.
4. Which of the following is the shortest length?
A) 30 km
B) 3.0 × 10-2 pm
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E) 3.0 × 108 nm
p. 16: Sect 1.4. Know the prefix of k, m, c, µ, n, p and f. The ones show in bold by heart.
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C) 3.0 × 103 m
D) 3.0 × 105 cm
5. Which of the following is the lowest temperature?
A) The freezing point of water
B) 105 °C
C) 30 °F
D) 80 K
E) The boiling point of water
p.p. 17-18: Sect 1.4. Know how to convert all temperature units to the identical one in
order to do the comparison; in this case it is K. Know how to use the temperature
formulas given in information sheet.
6. What is the mass (g) of a 30.0 mL liquid sample with density of 2.50 g/mL?
A) 20.0
B) 45.0
C) 0.50
D) 5.00
E) 75.0
p. 19: Sect 1.4. Memorize density = mass ÷ volume and know how to calculate the
volume through cross multiplication (i.e. volume = mass ÷ density)
7. Which of the following describes precision?
A) how close a measured number is to zero
B) how close a measured number is to the calculated value
C) how close a measured number is to other measured numbers
D) how close a measured number is to the true value
E) how close a measured number is to infinity
p. 22: Sect 1.5. Know the definition of accuracy and precision.
8. Which of the following has the same number of significant figures as the number
10.3100?
A) 1.2 × 106
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B) 199.791
C) 8.66
D) 5.119
E) 1000
p. p. 23-24: Sect 1.5. Memorize the rules of significant figures (i.e. significant digits).
9. Round the number 0.0007322 to two significant figures.
A) 0.00073
B) 0.000732
C) 0.000732
D) 0.00732
E) 0.007322
p. 25: Sect 1.5. Memorize the rounding rules and the rules of significant figures.
10. How many significant figures in the correct result of the following addition?
112.0
11.20
0.120
+ 0.0120
A) 7
B) 4
C) 5
D) 2
E) 3
p. 25: Sect 1.5. Memorize the addition-subtraction rule in handling significant figure.
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12. How many significant figures in the correct result of the following calculation?
(0.0045672)(100.7643)/38.45
A) 8
B) 6
C) 5
D) 4
E) 2
p. 25: Sect 1.5. Memorize the multiplication-division rule in handling significant figure.
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11. How many significant figures in the answer to the following computation?
(29.25 - 20.02)(1.80x 102)/1.450
A) 1
B) 2
C) 3
D) 4
E) 5
p. 25: Sect 1.5. Memorize the multiplication-division rule in handling significant figure.
This question involves two concepts: (1) addition-subtraction rule and (2)
multiplication-division rule.
13. Which of the three types of radioactivity characterized by Rutherford are
nonmatter?
A) β-rays
B) α-rays, β-rays, and γ-rays
C) γ-rays
D) α-rays and γ-rays
E) α-rays and β-rays
p. 45: Sect 2.2 Memorize the definition of matter and nonmatter (chap 1) and the three
types of radiations (chap 2).
14. How many protons, neutrons, and electrons respectively are there in Rn-222?
A) 86 p+, 86 n°, 136 eB) 86 p+, 136 n°, 86 eC) 86 p+, 222 n°, 86 eD) 222 p+, 86 n°, 222 eE) 34 p+, 34 n°, 29 ep. 49: Sect 2.3. Memorize the definition of atomic number (i.e. proton number) and mass
number, and know where to get the information from periodic table.
15. Which pair of atoms constitutes a pair of isotopes of the same element?
A) X
X
B)
X
X
C)
X
X
D)
X
X
E)
X
X
D) W
E) Na
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16. What is the element X for the symbol below?
184
X
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A) Ni
B) Cu
C) Au
p. 49: Sect 2.3.
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p. 49: Sect 2.3. Know the definition of isotopes.
17. What is the average atomic mass of the element X below? Identify this element.
Element X has three naturally occurring isotopes. The masses (amu) and % abundances
of the isotopes are given in the table below.
Isotope
24
X
25
X
26
X
Abundance (%)
78.99
10.00
11.01
Atomic mass (amu)
23.98504
24.98584
25.98259
A) 24.31, Mg
B) 24.31, Cr
C) 39.07, K
D) 38.64, Ar
E) 31.00, P
p. 51 [2.1] Sect. 2.4 & p. 53. Atomic weight (i.e. atomic mass) = ∑*(isotope mass) x
(fractional isotope abundance)] over all isotopes of the elements
18. Which pair of elements would you expect to exhibit the greatest similarity in their
physical and chemical properties?
A) H, Li
B) Al, As
C) K, Ca
D) He, Xe
E) S, Pm
p.p. 53- 54: Sect 2.5
19. What are the names for the elements in groups 2A, 6A, and 8A respectively?
A) alkaline earth metals, halogens, and chalcogens
B) alkali metals, chalcogens, and halogens
C) alkali earth metals, chalcogens, and noble gases
D) alkaline earth metals, transition metals, and halogens
E) halogens, transition metals, and alkali metals
p. 54: Sect 2.5.
20. Which one of the following molecular formulas is also an empirical formula?
A) C6H6
B) H2O
C) C3H6
D) CH3COOH
E) C6H14
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p. 56: Sect 2.6 Know the definition of empirical formula and molecular formula.
21. Which of the following compounds would you expect to be molecular compound?
A) Na2O
B) BaO
C) SrCl2
D) CO2
E) CaH2
p. 60: Sect 2.7 Know the definition of ionic compounds and molecular compounds.
22. Which species has 52 electrons?
A)
Xe+
B)
Te2-
C)
Sn4+
D)
Cd
E)
Xe2+
p. 56: Sect 2.7Sample Exercise 2.7. Application of p. 50.
23. Barium reacts with a polyatomic ion to form a compound with the general formula
Ba3(X)2. What would be the most likely formula for the compound formed between
sodium and the polyatomic ion X?
A) NaX
B) Na2X
C) Na2X2
D) Na3X
E) Na3X2
p.p. 58-62 Sect 2.7 Application of charges on ions. Memorize the charges of ions formed
by representative elements and the charges on several polyatomic ions (p.p. 63-67)
24. Which formula/name pair is correct?
A) NaHCO3 sodium carbonate
B) Mg(NO3)2 magnesium (II) nitrate
C) Mn(NO3)2 manganese(II) nitrate
D) Mg3N2
trimagnesium dinitride
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E) KOH
potassium oxygen hydrogen
p.p. 62-66: Sect 2.8 Memorize the rules of naming ionic compounds. Be aware the metals
that have multiple charges require specifying the charges in the naming.
25. Which formula/name pair is correct?
A) CaH2
calcium (II) dihydride
B) CH4
methane
C) H2CO3
dihydrogen carbonate
D) Al2O3
dialuminum trioxide
E) H2SO4
dihydrogen sulfurate
p.p. 62-68: Sect 2.8 Memorize the rules of naming ionic compounds, molecular
compounds, and acids. Be aware molecular compounds require prefixes.
26. Which formula/name pair is correct?
A) H2S (aq)
hydrogen sulfide
B) SF6
monosulfur hexafluoride
C) CH3COOH
acetic acid
D) HNO3
nitrous acid
E) N2O5
dinitrogen (V) pentaoxide
p.p. 62-68: Sect 2.8 Memorize the rules of naming ionic compounds, molecular
compounds, and acids.
27. What are the coefficients respectively when the following equation is balanced?
___ NaCl (aq) + ___ H2O (l) → ___ NaOH (aq) + ___ H2 (g) + ___ Cl2 (g)
A) 1, 1, 2, 2, 2
B) 1, 2, 1, 2, 2
C) 2, 2, 1, 1, 2
D) 1, 2, 2, 2, 1
E) 2, 2, 2, 1, 1
p.p. 82-87 Sect 3.1.
28. Which of the following is a combination reaction?
A) NH4Cl → NH3 + HCl
B) 2 MgO → 2MgO + O2
C) 2N2 + 3H2 → 2NH3
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p. 87-89: Sect 3.2 Memorize the definitions of combination, decomposition, combustion
and exchange reactions.
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D) 2CH4 + 4O2 → 2CO2 + 4H2O
E) Cd(NO3)2 + Na2S → CdS + 2NaNO3
29. What is the formula weight (amu) of ammonium phosphate, (NH4)2PO4, rounded
to the nearest integer?
A) 100
B) 131
C) 116
D) 132
E) 115
p.p. 89-90 Sect 3.3.
30. What is the mass % of H in methane (C12H22 O11)?
A) 25
B) 4.0
C) 7.8
D) 9.6
E) 6.4
p. 91. Sect 3.3. Sample Exercise 3.6.
31. How many H atoms are in 63 g of C6H12 O6?
A) 2.2 × 1023
B) 38
C) 2.53 × 1024
D) 4.4 ×1023
E) 9.5
p. 93: Sect 3.4 Sample Exercise 3.8
32-33. A compound contains 40.952% C, 4.58% H, and 54.50% O by mass.
32. What is the empirical formula?
A) C3H4O3
B) CHO
C) C6H8O6
D) C2H2O4
E) CHO2
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p. 99: Sect 3.5 (2016 Spring System Final) Sample Exercise 3.13.
33. The molar mass of the compound is 176.05 g/mol. What is the molecular formula of
this compound?
A) C3H4O3
B) CHO
C) C6H8O6
D) C2H2O4
E) CHO2
p. 99: Sect 3.5 (2016 Spring System Final) Sample Exercise 3.13.
34. – 37. The combustion of pentane (C5H12) in the presence of excess oxygen yields
CO2 and H2O:
____ C5H12 (g) + ____ O2 (g) → ____ CO2 (g) + ____ H2O (g)
34. What are the coefficients respectively after balanced the above reaction?
A) 4, 3, 5, 1
B) 3, 1, 4, 5
C) 4, 1, 3, 5
D) 6, 8, 1, 5
E) 1, 8, 5, 6
p.p. 82-86: Sect 3.1.
35. How many moles of CO2 will be produced when 4 moles of O2 are consumed in
their reaction?
A) 1.5
B) 3.0
C) 5.0
D) 6.0
E) 2.5
p.p. 103-108: Sect 3.6. Stoichiometric calculation.
36. How many moles of H2O will be produced when 12 mol of O2 react with 6 mol of
C5H12?
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A) 9.0
B) 36.0
C) 45.0
p.p. 106-108: Sect 3.7 Limiting Reactants. Sample Exercise 3.18 lists two methods to
solve the question: (1) dimensional analysis—via product-approaching method and (2)
Table method—via reactant-approaching method.
37. Which is the limiting reagent?
A) C5H12
B) H2O
C) O2
D) CO2
p.p. 107. Sect 3.7. Know the definition of limiting reactant (i.e. limiting reagent) and
excess reactant.
38. – 40. The combustion of methanol in the presence of oxygen yields CO2 and H2O:
____ CH3OH (l) + ____ O2 (g) → ____ CO2 (g) + ____ H2O (g)
38. What are the coefficients respectively after balanced the above reaction?
A) 4, 6, 4, 8
B) 4, 7, 4, 6
C) 2, 3, 2, 4
D) 4, 6, 7, 4
E) 4, 2, 2, 3
p.p. 82-86: Sect 3.1.
39. How many grams of CO2 will be produced when 45 g of methanol (CH3OH) react
with 90 g of oxygen?
A) 212
B) 178
C) 82.50
D) 61.88
E) 43.9
p.p. 106-108: Sect 3.7 Limiting Reactants. Sample Exercise 3.18 lists two methods to
solve the question: (1) dimensional analysis—via product-approaching method and (2)
Table method—via reactant-approaching method.
40. Which one is the excess reactant?
A) CH3OH
B) O2
p.p. 107. Sect 3.7. Know the definition of limiting reactant (i.e. limiting reagent) and
excess reactant.
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D) H2O
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C) CO2