Chemistry Semester Exam Review Sheet
1) What are fume hoods used for? Chemicals that produce toxic fumes
2) What safety equipment is needed for reactions involving high amounts of heat or possible explosions? Goggles, apron, gloves, fire extinguisher
3) What safety equipment should you use with the chemical described in the MSDS below?
goggles
apron
gloves
fume hood
4) How should you dispose of left over HCl? Dispose of chemicals as directed by the teacher
5) List 3 uses of science in the world today. Medicine, Forensics, Product Development
6) How can you prove or disprove a hypothesis? With experiments
7) Using standard lab equipment and acid, how can you determine if one piece of metal is more chemically reactive than another? Time how long it takes for the metal to dissolve
8) The true value of a measurement is 2.000. When three measurements are made they are recorded as 1.051, 1.052, and 1.053? Are the three measurements precise? Are they accurate?
These measurements are precise but not accurate.
9) Express 0.0234 in scientific notation.
2.34 x 10-2
10) Express the product of 561 and 1.2 using the correct number of significant digits. 670
11) Which of the graphs below show the relationship that would occur in container of gas on a hot day? The 4th graph – the pressure increases as the temperature increases
12)If the predominant color of the light spectrum of a gas is red what can you say about the magnitude of the wave’s energy, wavelength and frequency?
Red light has the lowest energy, lowest frequency and the longest wavelength.
13) List three possible pollution problems associated with nuclear power.
waste disposal, thermal pollution of lakes and streams, health hazards
14) Chemistry is the study of matter and how it behaves. This would help in any career field that dealt with the development of new materials.
15) Alcohol has a lower freezing and boiling point than water. Knowing this, what fluids used in your car might benefit from mixing alcohol with it? Windshield washer fluid in freezing climates
16)How did Dmitri Mendeleev organize his periodic table and how does this compare to our current periodic table? Mendeleev’s table was ordered by increasing atomic mass; the current
table is ordered based on inceasing atomic number.
17)What did J.J. Thompson discover? Give a brief explanation of his experiment. The electron
He used a cathode ray tube to shift negative particles towards a positive pole.
18) Iron rusting, food digesting, and wood burning are all examples of chemical changes.
19) Light activates photosynthesis in plants which is a chemical change.
20)Identify the following as an intensive or extensive property:
density intensive volume extensive
mass extensive boiling point intensive
21)Identify the following as a solid, liquid or gas:
particles have the highest kinetic energy gas
particles have the lowest kinetic energy solid
has no definite volume or shape gas
has no definite shape but has a definite volume liquid
has a definite volume and a definite shape solid
22)What happens to a laser light if it is shined through a colloid? Give an example.
the light will scatter; an example of a colloid is milk
23) How can you separate salt from salt water?
Evaporate the water
24) Draw a picture of what the particles of a heterogeneous mixture.
25)Mendeleev’s periodic table was based on increasing atomic mass.
26)Moseley’s periodic table (our current table) was based on increasing atomic number.
27)Which element would have similar chemicals properties to calcium: potassium or magnesium? Explain how you know that 2 elements are chemically similar.
Magnesium would have similar properties because it is in the same group as calcium.
28)Which direction does a period go on the periodic table?
Periods are horizontal on the periodic table.
29)Which direction does a group/family go on the periodic table?
Groups are vertical on the periodic table.
30)Where are metals located on the periodic table? Where are nonmetals located? Where are metalloids located? Metals are on the left of the staircase, nonmetals are on the right and
metalloids are on the staircase.
31)Identify 4 common properties of metals.
Ductile, malleable, good conductors of heat, good conductors of electricity
32)Identify 4 common properties of nonmetals.
Not ductile, not malleable, poor conductors of heat, poor conductors of electricity
33)Where are the transition metals located on the periodic table?
The transition metals are located in the center of the periodic table.
34)Categorize the following as metal, nonmetal or metalloid:
iron metal boron metalloid
aluminum metal chlorinenonmetal
silicon metalloid sulfur nonmetal
35)Define ionization energy.
Ionization energy is the amount of energy it takes to remove an electron.
36)Which element on the periodic table has the highest ionization energy?
Helium
37)High conductivity, low ionization energy, and low electronegativity would most likely indicate which of the following: metal or nonmetal Metals
38)Low conductivity, high ionization energy, and high electronegativity would most likely indicate which of the following: metal or nonmetal Nonmetals
39) Look at the table below. Elements 3, 11, and 19 have the lowest ionization energies. What else do they have in common? They are in the same group on the periodic table.
40) What did J.J. Thomson observe that led him to believe that the electron had a negative charge? It was attracted to a positive pole.
41)What is the frequency of the following wave? 2.5 cycles per second
42) A certain photon of light has a wavelength of 6.53 x 10-7 m. What is the frequency of its light?
Frequency = C / λFrequency = 3 x 108 / 6.53 x 10-7Frequency = 4.59 x 1014
43) What is the atomic mass of an element if 24.0% of its atoms have a mass of 176.00 g/mol, 41% have a mass of 178.00 g/moland 35% have a mass of 180.00 g/mol?
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Atomic mass = 176.00 x 0.24 + 178.00 x 0.41 + 180.00 x 0.35 = 178.22 g/mol
44)Identify the sublevel, energy level and number of electrons in the following: 2p6
energy level = 2sublevel = pnumber of electrons = 6
45)Draw electron dot diagrams for each of the following:
NitrogenChlorineCarbon
46) The element represented by 1s22s22p63s23p5 is chlorine.
47) Write the electron configuration for phosphorus. 1s22s22p63s23p3
48) Write the name for the following:
NH4Br ammonium bromide
Cu3(PO4)2copper (II) phosphate
CF4carbon tetrafluoride
SO2sulfur dioxide
49) Write the chemical formula for the following:
potassium chloride KCl
iron II sulfate FeSO4
sulfuric acid H2SO4
trinitrogen disulfide N3S2
50) Draw the electron dot diagram for the compound formed from lithium and bromine.
51) Draw the electron dot diagram for the compound carbon disulfide.
52)Metals tend to lose electrons to form ionic bonds.
53)Nonmetals tend to gain electrons to form ionic bonds.
54)Metals are ductile and malleable because they have a sea of electrons.
55)1 mole = 6.02 x 1023 particles.
56)1 mole = 22.4 liters
57)The molar mass of NaOH is: 40 g/mol
58)If 28% of a sample is Iron-55, 20% is Iron-56 and 52% is Iron-57, the average atomic mass of a sample of Iron would be 56.24 g. 55 x 0.28 + 56 x 0.20 + 57 x 0.52 = 56.24 g
59)How many moles are in 1.51 x 1024 atoms of carbon?
1.51 x 1024 atoms C x 1 mole C= 2.51 moles Carbon
6.02 x 1023atoms C
60)How many moles are represented by 30.3g of Neon gas?
30.3 g Ne x 1 mole Ne = 1.50 moles Ne
20.2 g Ne
61) The number of Na1+ ions necessary to make 4 moles of Na3PO4 would be 7.2 X 1024 Na+ ions.
(3 Na for each Na3PO4) (4 moles ) = 12 moles Na+
12 moles Na+ X 6.02 X 1023 Na+ ions
1 1 mole Na+
7.2 X 1024 Na+ ions.
62)What is the percent of oxygen found in MgO?
% O = mass of O x 100% O = 16.0 g x 100% O = 39.7 %
mass of MgO 40.3 g
63)If the percent of sodium in sodium oxide is 74%, what is the empirical formula for this compound?
74 g Na x 1 mole Na = 3.22 moles Na / 1.625 = 2 moles Na
23 g Na
26 g O x 1 mole O = 1.625 moles O / 1.625 = 1 mole O Empirical Formula = Na2O
16 g O
64)Balance each of the following equations:
_____C3H8 + 5O23CO2 + 4H2O
_____H2SO4 + 2NaOH _____Na2SO4 + 2H2O
2Cu + _____Pb(NO3)42Cu(NO3)2 + _____Pb
65)Describe the relative molecular motion for each of the states of water listed below:
ice molecules are less free to move steam molecules are more free to move
66)What is the Kinetic Theory of Matter?
The kinetic theory states that all tiny particles of matter are in constant motion.
67)How is water unique, as compared to other molecular compounds such as CO2?
Water is a polar molecule and therefore a very good solvent
68)Define the following:
polar molecule – has a separation of charge; electrons are shared unequally
nonpolar molecule – does not have a separation of charge; electrons are shared equally
69)Explain the phrase “like dissolves like.”
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Polar molecules dissolve other polar molecules
70)Based upon the graph at right; what mass of KNO3 will dissolve in 100g of water at 40oC? 60 grams
71)If you have a solution of 40g of LiBr at 80oC, would it be saturated, unsaturated or supersaturated?
unsaturated
72)If 30g of NaClO3 is dissolvedin 100g of water at 50oC, how much more can be dissolved to reach a saturated solution?
110 grams
73)What are three ways to make a sugar cube dissolve faster in water?
Stir the solution, crush the solute, heat the water
74)Define the following:
endothermic reaction –heat is absorbed; feels cold
exothermic reaction – heat is released; feels hot
75)Identify the type of reaction for each of the equations below:
HBr + NaOH NaBr + H2O double replacement
2Na + 2H2O 2NaOH + H2single replacement
3Mg(OH)2 + 2H3PO4 Mg3(PO4)2 + 6H2O double replacement
76) Identify the shape of the following molecules:
pyramidal tetrahedral linear
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