CHEM 1314 PRACTICE TEST #1 (ANSWERS ON LAST PAGE)
1) Which of the following statements is TRUE?
A) A scientific law is fact.
B) Once a theory is constructed, it is considered fact.
C) A hypothesis is speculation that is difficult to test.
D) An observation explains why nature does something.
E) A scientific law summarizes a series of related observations.
2) Give the name for SnO Note that tin forms several ions.
A) tin(I) oxide
B) tin(II) oxide
C) tin(III) oxide
D) tin(IV) oxide
E) tin monoxide
3) A substance composed of two or more elements in a fixed, definite proportion is
A) a homogeneous mixture.
B) a heterogeneous mixture.
C) a compound.
D) a solution.
E) an alloy.
4) Determine the name for N2O5.
A) dinitrogen pentoxide
B) nitrogen (II) oxide
C) nitrogen (II) oxide (V)
D) nitrogen (II) oxide
E) nitrogen tetroxide
5) Two or more substances in variable proportions, where the composition is variable throughout are
A) a solution.
B) a homogeneous mixture.
C) a compound.
D) an amorphous solid.
E) a heterogeneous mixture.
6) What answer should be reported, with the correct number of significant figures, for the following
calculation? (249.362 + 41) / 63.498
A) 4.6
B) 4.57
C) 4.573
D) 4.5728
E) 4.57277
7) All samples of a given compound, regardless of their source or how they were prepared, have the
same proportions of their constituent elements. Which law does this refer to?
A) Law of Definite Proportions
B) Law of the Conservation of Mass
C) Law of Modern Atomic Theory
D) Law of Multiple Proportions
E) First Law of Thermodynamics
8) Identify the smallest subatomic particle.
A) a neutron
B) an electron
C) a proton
D) an alpha particle
E) a nucleus
9) What does "X" represent in the following symbol?
X
A) silicon
B) sulfur
C) zinc
D) ruthenium
E) nickel
10) Determine the number of protons, neutrons, and electrons in the following:
X
A) p+ = 12
B) p+ = 12
C) p+ = 12
D) p+ = 25
E) p+ = 12
n° = 25
n° = 12
n° = 13
n° = 12
n° = 13
e- = 12
e- = 13
e- = 12
e- = 13
e- = 25
11) Which of the following statements about isotopes is TRUE?
A) Isotopes of the same element differ only in the number of electrons they contain.
B) An isotope of an atom with a larger number of neutrons is larger than an isotope of the same atom
that contains fewer neutrons.
C) Isotopes of the same element have the same mass.
D) Isotopes of the same element don't usually have the same properties.
E) Isotopes of the same element differ only in the number of neutrons they contain.
12) Which of the following properties is an extensive property?
A.
Freezing point
B.
Color
C.
Volume
D.
Hardness
E.
Density
13) In a chemical reaction, matter is neither created nor destroyed. Which law does this refer to?
A) Law of Definite Proportions
B) Law of the Conservation of Mass
C) Law of Modern Atomic Theory
D) Law of Multiple Proportions
E) First Law of Thermodynamics
14) While speaking to a colleague, a scientist makes the following statement: "I propose that Bald
Eagle eggs in northern Maine will have thinner shells than those from birds in southern Alaska due to
increased levels of pesticides in the water." This statement is an example of a:
A)
Theory
B)
Law
C)
Conclusion
D)
Hypothesis
E)
Political statement
15) What element is defined by the following information?
p+ = 20 n° = 20 e- = 20
A) zirconium
B) calcium
C) potassium
D) neon
E) argon
16) A student performs an experiment to determine the density of a juice. She obtains the following
results: 1.01 g/mL, 1.51 g/mL, 2.15 g/mL, 2.34 g/mL. If the actual value for the density of the sugar
solution is 1.75 g/mL, which statement below best describes her results? (Hint: for part of the answer
you will need to calculate an average)
A)
The student’s results are precise, but not accurate
B)
The student’s results are both precise and accurate
C)
The student’s results are neither precise nor accurate
D)
The student’s results are accurate, but not precise
E)
It isn't possible to determine with the information given
17) How many significant figures are in the measurement, 0.02030 Kg?
A) One
B) Two
C) Three
D) Four
E) Five
18) What answer should be reported, with the correct number of significant figures, for the following
calculation? (49.2685 - 48.10) / 50.000
A) 0.02337
B) 0.0234
C) 0.023370
D) 0.023
E) 0.02
19) When 3.21 g of a compound containing only silicon and hydrogen is burned completely in oxygen,
it yields 6.01 g of silicon dioxide and 7.21 g of water. How much oxygen (in g) is used up in this
reaction?
A) 4.00 g
B) 3.01 g
C) 10.01 g
D) 4.41 g
E) 2.01 g
20) Which is a correct description of the organization of subatomic particles in atoms?
A) Protons and electrons are tightly packed into a small nucleus. Neutrons occupy the space
outside the nucleus.
B) Neutrons and electrons are tightly packed into a small nucleus. Protons occupy the space
outside of the nucleus.
C) Protons and neutrons are tightly packed into a small nucleus. Electrons occupy the space
outside the nucleus.
D) Electrons are tightly packed into a small nucleus. Protons and neutrons occupy the space
outside of the nucleus.
E) A sea of positive charge with clumps of electrons throughout it like a plum pudding
21) How many neutrons are in this isotope of tin?
A)
B)
C)
D)
E)
50
116
176
182
66
##$
!"Sn
22) When a 15.75 gram sample of titanium is placed in a graduated cylinder containing 20.0 mL of
water, the water level rises to 23.5 mL. What is the density of titanium in g/cm3? (Note: 1 ml = 1 cm3)
A) 3.9 g/cm3
B) 3.7 g/cm3
C) 0.67 g/cm3
D) 0.79 g/cm3
E) 4.5 g/cm3
23) What is the proper name for AlCl3?
A) aluminum (III) chloride
B) aluminum chloride
C) aluminum (III) chlorate
D) aluminum (III) chlorite
E) aluminum trichloride
24) What is the chemical formula for vanadium(V) oxide?
A)
B)
C)
D)
E)
VO5
V5 O2
V5 O
V2 O3
V2 O5
25. What is the charge of the cation in WO3?
A) 6+
B) 2+
C) 3+
D) 4+
E) 2-
1. E
2. B 3. C 4. A
14. D 15. B 16. D 17.D
5. E
6. B 7. A 8. B
18. B 19. C 20. C 21. E
9. A
22. E
10. C 11. E. 12. C 13. B
23. B 24. E 25. A