Transcript 1st Semester Exam in High School Chemistry

1st Semester Exam in High
School Chemistry
Examination in January of 2012
1. Substance A is a liquid, Substance B
is a gas and Substance C is a solid.
All of the substances are at the same
temperature and pressure. Which of the
following shows the correct relationship
between the strength of the intermolecular
forces in each substance?
A. A > B > C
B. B > A > C
C. C > B > A
D. C > A > B
2. A balloon is inflated with room temperature air,
and is placed outside in the sun. The balloon
expands due to the rise in temperature. Which of
the following describes what happens to the
molecules of air as the temperature rises?
A. The molecules of air stop colliding with the
balloon wall.
B. The molecules of air increase in size.
C. There are fewer interactions between the air
molecules.
D. The molecules of air move more quickly.
3. Condensation occurs when
_____________________ .
A. a gas loses energy to become a liquid
B. a solid gains energy to become a liquid
C. a liquid gains energy to become a gas
D. a gas loses energy to become a solid
4. As liquid carbon dioxide freezes, its molecules
________________ .
A. absorb heat energy and move farther apart
B. absorb heat energy and move closer together
C. release heat energy and move farther apart
D. release heat energy and move closer together
5. Compared to the particles in a gas, the
particles in a solid move_____________ .
A. at the same speed as the gas
B. quicker and farther than the gas
C. quicker than the gas
D. slower than the gas
6. Which one of the following is a TRUE
statement?
A. Gas molecules move around freely.
B. Liquids do not change shape easily.
C. Gas molecules move more slowly as they are
heated.
D. Solids change shape easily.
7. Which of the following BEST describes what
happens when most substances change from
a solid state to a liquid state?
A. The molecules slow down.
B. The molecules move farther apart.
C. The molecules get smaller.
D. The molecules lose energy.
8. Unlike most substances, water is unusual
because it ____ when it goes from the liquid
to solid state.
A. contracts
B. melts
C. expands
D. diffuses
9. Which of the following is an example of a
chemical change?
A. filling a balloon with helium
B. freezing a glass of water
C. a plant collecting energy from the sun to
create food
D. a dog ripping a newspaper
10. What happens to the atoms of the reactants
in a chemical reaction?
A. They change into new atoms.
B. They recombine to form the products.
C. They change names.
D. Some are lost to the environment.
11. When two substances react chemically, what type of
products will be formed?
A. Products will be very similar to the reactants.
B. Products will be very different from the reactants.
C. The products will vary from one reaction to another.
D. Products of a chemical reaction cannot be predicted.
12. A good hypothesis _____________ .
A. can be tested by experiment
B. can be an educated guess predicting the
outcome of an experiment
C. can only be formed when you know
something about what is going to happen
D. may be described by all of the above
13. In the late nineteenth century, Dmitri
Mendeleev spent two years developing a table
that could be used to predict which of the
following?
A. age of mineral samples
B. movements of planets
C. composition of stars
D. properties of elements
14. Is science limited only to ideas and concepts
that are testable?
A. Yes, because scientists can only make theories
about things that have been measured.
B. Yes, because scientists cannot create new
theories from nothing.
C. No, because natural phenomena can be
observed, but not always measured.
D. No, because scientific theories change as
public opinion changes.
15. Which family correctly labels the elements in
Group 1 on the Periodic Table?
A. transition metals
B. alkali series
C. lanthanide elements
D. actinide series
16. Which is the BEST conclusion that can be made from the
information shown on the graph below?
A. Electrons in Period 3 are more difficult to remove from an atom
than electrons in Period 2.
B. In general, going from left to right across a period on the Periodic
Table, electrons become increasingly difficult to remove from an
atom.
C. Period 2 atoms are larger in size than Period 3 atoms, decreasing the
attraction of the valence electrons for the nucleus.
D. As the number of valence electrons increases, the electron removal
energy decreases.
17. Melting Point of Elements
Use the data shown below to create a graph on
the element’s melting point.
Element
Lithium
Beryllium
Boron
Carbon
Nitrogen
Oxygen
Fluorine
Neon
Potassium
Magnesium
Aluminum
Silicon
Phosphorus
Sulfur
Chlorine
Argon
Melting Point (oC)
186
1290
2200
3500
- 210.5
-218.4
-223
-253
63
649
659
1434
44
112.8
-102
-190
Students should make a bar graph of the data.
18. Explain how the melting point of a metal
compares to the melting point of a nonmetal.
18. The melting point of a
metal is generally higher,
except for the nonmetal that
is next to the metalloid.
19. Why is an atom considered electrically neutral?
A. neutrons equal the number of protons
B. proton forces pull on the neutrons
C. electrons equal the number of protons
D. electrons equal the number of neutrons
20. Which of the following statements describes
isotopes of an atom?
A. different chemical properties
B. different numbers of protons
C. different masses
D. different numbers of electrons
21. Using the Periodic Table, predict which elements will
have similar chemical properties or reactivity.
A. cadmium, calcium and carbon
B. magnesium, strontium and barium
C. rubidium, yttrium and zirconium
D. nitrogen, sulfur and bromine
22. Choose the correct Lewis Dot diagram for
NaCl.
A.
B.
C.
D.
23. As the atomic number increases, within a
group of elements, the atomic radius usually
________________ .
A. decreases
B. remains the same as the one above it
C. increases
D. decreases, then increases
24.Which of the following increases as the
electronegativity difference between 2 atoms
increases?
A. ionic nature of the bond
B. covalent nature of the bond
C. metallic nature of the bond
D. electron sharing between the 2 atoms
25.What is the formula for potassium fluoride?
A. KF
B. KF2
C. K2F
D. K2F2
26. What is the formula for the compound
formed by iron (II) ions and chromate ions?
A. FeCrO4
B. Fe2CrO4
C. Fe2(CrO4)3
D. Fe(CrO4)2
27. What is the formula for aluminum
hydroxide?
A. AlOH
B. Al(OH)3
C. A l2(OH)3
D. A l3OH
28. What is the name of the compound: N2O3?
A. sodium dioxide
B. dinitrogen oxide
C. nitrous oxide
D. dinitrogen trioxide
29. What is the formula for tin (IV) oxide?
A. Tn4O2
B. SnO
C. TnO2
D. SnO2
30. What is the formula for barium nitrate?
A. Ba(NO3)2
B. BaNO2
C. Ba2NO3
D. Ba(NO4)2
31. What is the name of the compound AlPO4?
A. aluminum phosphide
B. aluminum phosphate
C. aluminum phosphite
D. aluminum phosphoroxide
32. Which of the following is the metallic ion in
scandium (II) chloride?
A. Sd 2 +
B. Cl 2C. Sc 2 +
D. Cl 1-
33. Using the Nutrition Facts label to the right,
which of the following formulas is CORRECT
for the highlighted ingredient?
A. Na2PO3
B. Na3PO4
C. NaPO
D. Na3(PO4)2
34. Select the correct name for this compound.
A l2(SO4)3
A. dialuminum trisulfate
B. aluminum trisulfide
C. aluminum sulfate
D. sulfuric aluminate
35. Choose the correct name for the following.
HClO3
A. hydrogen chloroxide
B. hydrogen trichlor
C. hypochlorite
D. chloric acid
36. What is the name of the compound NiSO4 ?
A. nickel (II) sulfite
B. nickel (II) sulfide
C. nickel (II) sulfate
37. What is the oxidation number of nitrogen in
most compounds?
A. -3
B. -2
C. -1
D. + 1
38. What is the oxidation number of hydrogen in
HCl?
A. 0
B. +1
C. + 2
D. + 3
39. Name the compound. H2O
A. dihydrogen monoxide
B. hydrogen oxide
C. hydrogen oxalate
D. hydrogen dioxide
40. Name the following. Li2S
A. dilithium monosulfide
B. lithium sulfide
C. lithium disulfide
D. sulfuric lithate
41. Which of the following is a possible
compound formed from Calcium (2+) and the
polyatomic ion Nitrate, NO3 (-1)?
A. Ca2NO3
B. Ca3NO2
C. CaNO
D. Ca(NO3)2
42. Carbon tetrachloride is a solvent which is used as a
refrigerant and also as a cleaning agent. Prior to the
1950s, carbon tetrachloride was manufactured by the
chlorination of carbon disulfide: CS2 + 3 Cl2 → CCl4 +
S2Cl2 but now it is mainly produced from methane: CH4
+ 4 Cl2 → CCl4 + 4 HCl How many grams of carbon
tetrachloride can be produced from reacting 709.0
grams of Chlorine (Cl2) with excess methane?
A. 3.845 g
B. 61.53 g
C. 384.5 g
D. 6153 g
43. What is the coefficient for potassium in the
balanced equation?
____ Na + ____K2S → ____ K + ____ Na2S
A. 2
B. 4
C. 6
D. 8
44. For the reaction HCl + NaOH > NaCl + H2O,
which reactant is the limiting reactant given
100.0 g of sodium hydroxide and 100.0 g of
hydrochloric acid?
A. hydrochloric acid
B. sodium hydroxide
C. sodium chloride
D. water
45. In the reaction A + B → C + D, if element B is
in excess, then —
A. A is the limiting reactant.
B. B is the limiting reactant.
C. C is the limiting reactant.
D. both A and B are limiting reactants.
46.In the reaction 2RbNO3 → 2RbNO2 + O2 how
many moles of O2 are produced when 5.0
mol of RbNO3 decompose?
A. 1.0 mol
B. 2.5 mol
C. 3.0 mol
D. 7.5 mol
47. How many molecules are represented by
3.00 moles of oxygen, O2?
A. 4.98 x 1024
B. 3.00
C. 6.32 x 102 1
D. 1.81 x 1
48. White phosphorous is used as an incendiary weapon and
smoke tracer. It can also be used to create smoke screens to
mask troop movement or hide platoon position. Robert
Boyle was the first to use phosphorus to ignite sulfur tipped
wooden splints, forerunners of our modern matches, in
1680. One of the ways in which it can be made involves the
fusion of calcium phosphate with carbon and sand in an
electric furnace.
2Ca3(PO4)2 + 6SiO2 + 10C → 6CaSiO3 + P4 + 10CO
Starting with 100.0 grams of calcium phosphate and
assuming excess silicon dioxide and carbon, how many
moles of phosphorous will be produced?
A. 0.1612 moles
B. 0.3224 moles
C. 15510 moles
D. 1.551 moles
49. Calcium hydroxide and hydrochloric acid react to form
calcium chloride and water as shown in the chemical
reaction. If the chemicals are present in exactly the
correct ratios to fully use all of the ingredients, how
many moles of water would be formed from 5 moles of
HCl?
__ Ca(OH)2 + __ HCl → __ CaCl2 + __
H2O
A. 1 mole
B. 2 moles
C. 5 moles
D. 10 moles
50. How many moles are in 75.0 grams of
nitrogen gas – N2?
A. 3.00 moles
B. 0.333 moles
C. 2.68 moles
D. 4.52 x 102 5 moles
51. In the reaction, 2 H2 + O2 → 2 H2O, what is
the mole ratio of hydrogen to water?
A. 2: 2
B. 2 : 1
C. 1 : 2
D. 4 : 4
52. Baking soda (sodium bicarbonate) is a compound
commonly used in baked goods, as a deodorizer in
refrigerators and as an antacid. Commercial quantities
of baking soda are produced by mixing soda ash
dissolved in water with carbon dioxide. Baking soda
precipitates as a solid from this method: Na2CO3 + CO2
+ H2O → 2 NaHCO3
How many grams of soda ash would be needed to
produce 1.00 kg of sodium bicarbonate?
A. 396 grams
B. 631 grams
C. 1270 grams
D. 1590 grams
53. In the reaction 2 H2 + O2 → 2 H2O, how many
moles of oxygen are required to fully react
with 6.0 mol of hydrogen?
A. 3.0 mol
B. 6.0 mol
C. 12.0 mol
D. 18.0 mol
54. Tell what is wrong with each of the following
molecular formulas and write the correct
formula.
what is wrong
SOO (sulfur dioxide)
2HO (Hydrogen peroxide-two hydrogen atoms
and two oxygen atoms)
correct formula
55. Determine the number of electrons and
protons contained in an atom of the following
elements:
electrons protons
sulfur
As
element number 24
Hydrogen ion H+
Potassium Cation
56. Write isotope symbols for atoms with the
following characteristics.
Contains 18 electrons
and 20 neutrons
A calcium atom with a
mass number of 40
An arsenic atom that
contains 42 neutrons
38Ar
18
40Ca
20
75As
33
57. What is the symbol and name for the
element whose average atoms have a mass
very close to three times the mass of an
average beryllium atom?
Al
58. Determine the molecular weights of the
following in amu:
NAME
FORMULA MOLECULAR WEIGHT in amu
fluorine
(F2)
38
carbon disulfide (CS2)
76
sulfurous acid
(H2SO3)
82
ethyl alcohol
(C2H6O)
46
ethane
(C2H6)
30
59. The molecular weight is determined for a gas
that is known to be an oxide of nitrogen. The
value obtained experimentally was 43.98 u.
Which of the following is most likely to be the
formula of the gas?
A. NO
B. N2O
C. NO2
D. NO3
60. Which of the following may not be classified
as matter
A. Sand
B. Heat
C. Seawater
D. Our atmosphere
61. Perform the following calculation and
express the answer to the right number of
significant figures
1222 g
2 mL
A.
B.
C.
D.
611 g/mL
6.110 x 102 g/mL
6.1 x 102 g/mL
6 x 102 g/mL
62. Perform the following calculation and
express the answer to the right number of
significant figures
1.89  13 .957
5 .1
A. 3.10
B. 3.1073
C. 3.1
D. 3.11
63. Which of the following correctly converts
0.000001546 in scientific notation?
A. 1.546 x 106
B. 1.546 x 105
C. 1.546 x 10-5
D. 1.546 x 10-6
64. Of the following elements, __________ has
the most negative electron affinity.
A. P
B. Al
C. Si
D. Cl
E. B
65. There are ____ electrons, __ protons, and
___ neutrons in an atom of
Xe.
A. 132, 132, 54
B. 54, 54, 132
C. 78, 78, 54
D. 54, 54, 78
66.__________-rays consist of fast-moving
electrons.
A. alpha
B. beta
C. gamma
D. X E. none of the above
67. Consider the following selected postulates of Dalton's atomic theory:
(i) Each element is composed of extremely small particles called atoms.
(ii) Atoms are indivisible.
(iii) Atoms of a given element are identical.
(iv) Atoms of different elements are different and have different properties.
Which of the postulates is(are) no longer valid?
A. (i) and (ii)
B. (ii) only
C. (ii) and (iii)
D. (iii) only
E. (iii) and (iv)
68. Isotopes are atoms that have the same
number of ___ but differing number of ___.
A. protons, electrons
B. neutrons, protons
C. protons, neutrons
D. electrons, protons
E. neutrons, electrons
69. An atom of the most common isotope of
gold, Au, has ___ p+, ___ no, and ___e-.
A. 197, 79, 118
B. 118, 79, 39
C. 79, 197, 197
D. 79, 118, 79
70. Of the following, the smallest and lightest
subatomic particle is the ________.
A. neutron
B. proton
C. electron
D. nucleus
E. alpha particle