Download 2nd Semester final review

2013 Final Exam Review Sheet
1. What is a family or group on the periodic table and what is so important about it.
Elements in a family or group (an up-down column) share similar chemical properties
2. Complete the chart below:
Symbol
Protons
C-14
6
Na-24
11
Electrons
6
10
Neutrons
8
13
Charge
0
+1
3. The following is a trend of the first ionization energies of a family.
Na: 5.14
K: 4.34
Rb: 4.1 Cs: 3.89 Predict the value for Rb.
(really anything reasonably between 4.34 and 3.89)
4. Define element, compound, and mixture.
An element is only 1 kind of atom
A compound is two or more elements chemically combined into a new substance that forms a
new substance with new chemical properties
A mixture is created when two or more elements or compounds are combined together but do not
form a new substance but retain their original properties.
5. Describe each of the diagrams below as either:
A) Element
B) Compound
C) Mixture of elements
D) Mixture of compounds
E) Mixture of elements and compounds
B
A
C
E
D
6. What is the difference between a physical and a chemical change?
Physical: the substance has not changed its formula, just its shape, size, state, etc.
Chemical: the substance has turned into a brand new thing
7. For each of the following, decide whether they are: easy to separate, hard to separate, or
impossible to separate.
elements, compounds, homogeneous mixtures, heterogeneous mixtures.
Impossible hard
easy
easy
8. What is the difference between heat and temperature?
Heat is total energy of a system
Temperature is the average kinetic energy of the particles (how fast they move)
9. Write out the spectroscopic notation for:
a. V: [Ar] 4s23d3
b. Br: [Ar] 4s23d104p5
c. Ba: [Xe] 6s2
d. N: [He] 2s22p3
10. How many valence electrons are in:
a. Mg: 2
b. C: 4
c. S: 6
d. I: 7
11. Define a valence electron outmost electrons in an atom
12-14. Name the following ionic compounds:
a. Na2SO4 sodium sulfate
b. CaCl2 calcium chloride
c. (NH4)3PO4 sodium sulfate
d. Fe2O3 iron (III) oxide
e. FeBr2 iron (II) bromide
15. For each combination below, decide if a PPT forms. If it does, write its formula:
a. KI + Mg(NO3)2 no PPT
b. CaCl2 + Na2CO3 PPT CaCO3
c. Al(NO3)3 + K2CrO4 PPT Al2(CrO4)3
d. LiClO3 + (NH4)2SO4 no PPT
16. What is the difference between an ionic bond and a covalent bond?
Ionic bonds are metals and non-metals that exchange electrons and make crystals
Covalent bonds are non-metals only that share electrons and make molecules
17. Name the following covalent compounds:
a. N2O4 dinitrogen tetroxide
b. P2O diphosphorous monoxide
c. S2Cl2 disulfur dichloride
d. BrF bromine monofluoride
18. Draw the Lewis Dot structures for:
a. NH3
b. CCl4
H
N H
c. SiO2
d. CCl2O
H
Cl
Cl
C
O
Cl
Si
O
O
Cl
C
Cl
Cl
19. Decide whether each substance below would dissolve better in H2O (polar) or C6H6 (nonpolar)?
a. C2H5OH water
b. C10H8 C6H6
c. C12H26 C6H6
d. CH3OH water
3 pigs = 14 chickens 3 goats = 2 sheep
1 cow = 2 donkeys 12 rabbits = 1 duck
1 sheep = 2 pigs
3 donkeys = 1 horse 3 ducks = 8 chickens 2 oxen = 5 horses
20. How many ducks can be traded for 64 chickens?
3 ducks
8 chickens
64 chick
1
= 24 ducks
21. How many pigs can be traded for 54 goats?
2 pigs
1 sheep
2 sheep
3 goats
54 goats
= 72 pigs
1
22. How many minutes are in 3 days?
60 min
1 hr
24 hrs
1 day
3 days
= 4320 min
1
23. How many mm are in 17 feet? (1 inch = 2.54 cm
10 mm
1 cm
2.54 cm
1 in
12 inch
1 foot
10 mm = 1 cm 12 inches = 1 ft)
17 feet
= 5181.6 mm
1
24-26. For each substance below, calculate the molar mass (in g/mole):
a. Cu
63.5
b. I2Cl7
502.3
c. Sr(HCO3)2 209.6
27. What is a mole? What is it useful for counting?
A mole is a chemistry counting unit for counting very tiny things like atoms or molecules. It is
6x1023 of something
28-31. Using a mole map, calculate each of the following:
a. how many moles are in 5x1023 atoms of potassium 0.833 moles
b. how many molecules are in 4.3 moles of H2O 2.58x1024 molecules
c. how many moles are in 100 g of CO2 2.27 moles
d. how many atoms are in 200 g of Xe 9.14x1023 atoms
32, 36. Using a mole map, solve each of the following:
a. What is the molarity when 10 moles are dissolved in 4 Liters? 2.5 moles/L
b. What is the molarity when 150 g of MgCl2 (molar mass 95.3 g = 1 mole) are dissolved
in 750 mL of solution 2.1 moles/L
33-35. Using a mole map, solve each of the following:
a. How many moles are dissolved in 2.4 L of a 3.6 M solution 8.64 moles
b. How many mL of 0.75 M solution can be made with only 1.2 moles 1600 mL
c. How many mL are needed to dissolve 100 g of CH3OH (molar mass 32 g = 1 mole)
into a 3.6 M solution 868 mL
37. What is the difference between a solute, a solvent, and a solution?
Solute is the substance being dissolved (often solid)
Solvent is the substance doing dissolving (usually liquid)
Solution is the mixture of the two
38. Why do equations have to be balanced in the first place?
Atoms can’t be created or destroyed. Only rearranged.
39-42. Balance each of the following equations:
1 CaCl2 + 2 AgNO3  1 Ca(NO3)2 + 2 AgCl
1 C2H5OH + 3 O2  2 CO2
+ 3 H2O
2 Na3PO4 + 3 MgCl2  6 NaCl + 1 Mg3(PO4)2
16 Rb + 1 S8  8 Rb2S
3 C + 2 Fe2O3  4 Fe + 3 CO2
43-44. Write the formulas the substances below and balance the equations:
copper (II) nitrate + magnesium  magnesium nitrate + copper
Cu(NO3)2 + Mg  Mg(NO3)2 + Cu
Magnesium oxide  magnesium +
oxygen
2 MgO  2 Mg + O2
Water + sulfur trioxide  hydrogen sulfate
H2O + SO3  H2SO4
Potassium chromate + magnesium chloride  potassium chloride + magnesium chromate
K2CrO4 + MgCl2  2 KCl + MgCrO4
45-47. Determine whether each reaction below is synthesis, decomposition, single replacement,
double replacement, or combustion:
Decomposition
2 CuO  2 Cu + O2
Double Replacement Mg(NO3)2 + Ba(OH)2  Mg(OH)2 + Ba(NO3)2
Synthesis
2 Al + 3 Br2  2 AlBr3
Single Replacement Fe + 3 AgNO3  Fe(NO3)3 + 3 Ag
Combustion
2 C8H18 + 25 O2  16 CO2 + 18 H2O
48-49. Predict the products of the following equations:
4 K + 1 O2  2 K2O
1 Fe2O3 + 3 H2  2 Fe + 3 H2O
3 CaCl2 + 2 Li3PO4 
1 Ca3(PO4)2 + 6 LiCl
2 NaCl  2 Na + Cl2
1 CH4 + 2 O2  CO2 + 2 H2O
50-51. For each substance below, calculate the mass % of the atom that is underlined:
a. K2Cr2O7
38.1%
b. (NH4)3PO4
8.05%
c. Al2O3
52.9%
52. An alcohol solution is made by adding 40 g of alcohol to 100 grams of water. What is the
mass % of each substance in the solution?
Alcohol: 40/140 *100% = 28.6%
Water: 100.140 *100% = 71.4%
53. A bag of popcorn has a mass of 115 grams before popping. After popping, the bag has a
mass of 90 grams. What is the mass % of the water in the popcorn?
25/115 *100% = 21.7%
54. For the equation:
H2SO4 + 2 NaOH  2 H2O + Na2SO4
how many moles of H2SO4 are needed to completely react with 10 moles of NaOH?
1 mole HsSO4
2 mole NaOH
10 mole
NaOH
= 5 moles H2SO4
1
55. Based upon the following equation:
2 Na + 2 H2O  2 NaOH + H2
How many grams of hydrogen gas could be generated from 150 grams of sodium?
1 mole Na 150 g Na
2 g H2
1 mole H2
= 6.5 g H
2
1 mole H2
23 g Na
2 mole Na
1
56. According to the balanced equation below, how many grams of Fe (molar mass 55.8
g/mole) could be reacted with 2.3 L of 0.05 M AgNO3?
Fe + 3 AgNO3  Fe(NO3)3 + 3 Ag
55.8 g Fe
1 mole Fe
1 mole Fe
3 mole AgNO3
0.05 mole
AgNO3
1 L AgNO3
2.3 L AgNO3
= 2.14 g Fe
1
57. According to the balanced equation below, how many mL of 3 M H2SO4 would be
necessary to react with 125 grams of KOH (molar mass 56.1 g/mole)?
H2SO4 + 2 KOH  K2SO4 + 2 H2O
1000 mL
H2SO4
1 L H2SO4
1 L H2SO4
3 moles H2SO4
1 mole H2SO4
2 mole KOH
1 mole KOH
56.1 g KOH
125 g KOH
1
= 371 mL of
H2SO4
58. What is the definition of pressure? How does it help explain things like knives, high heels,
or snowshoes.
P = Force/Area
Knives and high heels have their force exerted over a very small area so
pressure is very high. Snowshoes have their force exerted over a very large area so pressure is
small.
59. How does a barometer work?
An evacuated tube filled with mercury has atmospheric pressure pressing on it. On high pressure
days, the mercury goes up. On low pressure days it goes down.
60. What is the relationship between pressure and altitude?
As altitude increases, pressure decreases.
61-62. Convert each of the following pressures:
a. 150 kPa to Torr 1125 Torr
b. 2.4 Atm to psi 35.3 PSI
c. 500 mm Hg to atm 0.66 atm
63-64. Convert each of the following temperatures:
a. 50 oC to K
323 K
b. -40 oC to K
233 K
o
c. 400 K to C
127 oC
d. 200 K to oC
-73 oC
65-66. What is the difference between Kelvin and Celcius scales? What is the lowest
temperature you can go to?
Kelvin has no negative numbers. The smallest Kelvin temperature is zero which is -273 oC
67-68. Characterize solids, liquids, and gases for their ability to keep their shape and volume.
Solids: keep shape and volume
Liquids: keep volume but not shape
Gases: keep neither shape nor volume
69-70. Give an example of Boyle’s Law, Charles’ Law, and Gay-Lussac’s Law.
Boyles: A balloon in a bell jar gets bigger when the air is sucked out
Charles: A hot air balloon gets bigger when you heat it
Gay-Lussacs: An aerosol can explodes when thrown into the campfire
71-77. Answer the following questions:
a. If a sample of gas is at 15 oC and 350 mm Hg and 3.2 L, what temperature (in Kelvin
and oC) would the pressure be at 111.8 mm Hg and 9.5 L?
P1 V1
T1
= P2 V2
T2
350 mm Hg x 3.2 L =
288 K
111.8 mm Hg x 9.5 L
T2
T2 = 273 K or 0 oC
b. A gas has a volume of 200 L at a pressure of 50 kPa. What is the pressure if the gas is
allowed to expand to 400 L at constant temperature?
P1 V1
= P2 V2
50 kPa x 200 L = P2 x 400 L
P2 = 25 kPa
c. When 60 mL of a gas at 50 oC is heated until the gas reaches 900 oC, what is the new
volume if pressure is constant?
218 mL
V1 = V2
T1
T2
60 mL = V2
V2 = 218 mL
323 K
1173 K
d. What are standard temperature and pressure?
0 oC = 273 K and
760 mm Hg = 760 Torr = 101.3 kPa = 1 atm = 14.7 PSI
78-80. Know the properties of acids and bases. How do they: taste, feel, affect litmus, affect
phenolphthalein, etc.
Acids: taste sour, turn litmus red, turn phenolphthalein colorless
Bases: taste bitter, feel slippery, turn litmus blue, turn phenolphthalein pink
81-82. For each reaction below label: acid, base, conjugate acid, conjugate base:
H2PO4-1
+
NH3 
NH4+ +
HPO4-2
A
CO3-2
B
+
B
CA
CB
HSO3-1 
HCO3-1 +
SO3-2
A
CA
CB
83-84. Name the following acids or bases:
a. HClO3 chloric acid
b. HBr
hydrobromic acid
c. HF
hydrofluoric acid
d. H2SO3 sulfurous acid
e. Mg(OH)2 magnesium hydroxide
85-86. If the number below is in decimal form, write it in scientific notation and vice versa:
a. 0.000 000 072 3
7.23 x10-8
b. 0.004 56
4.56x10-3
-8
c. 4.5x10
0.000000045
d. 2.3x104
23000
87. Know what numbers are acidic, basic, and neutral on the pH and pOH scales.
pH: acid <7
neutral = 7
base > 7
pOH: base <7
neutral = 7
acid >7
88. If a solution is a pH of 2 and another is a pH of 8, which is more acidic and by how many
times?
pH 2 is 1,000,000 times more acidic
89. Why is the pH scale special? It is a logarithmic scale. Every change of 1 actually changes
by 10
90-94. Fill in the boxes below:
[H+]
2.3x10-4
pH
3.6
pOH
10.4
[OH-1]
4.3x10-11
3.9x10-6
5.4
8.6
2.5x10-9
6.3x10-8
7.2
6.8
1.6x10-7
1.3x10-2
1.9
12.1
8.5x10-13
95. How does acid rain work? What are the main causes of it?
Pollutants such as sulfur and nitrogen oxides rise into the air and react with the water in the
clouds. They turn acidic and rain down on us. Burning fossil fuels causes acid rain.
96-97. A solution turns blue in bromphenol blue, pink in methyl orange, and yellow in cresol red.
What is the likely pH of the solution? 4
R = red
Y = yellow
B = blue
P = pink
O = orange
Pu = purple
C = colorless
2
3
4
5
6
7
8
Cresol Red
Y
Y
Y
Y
Y
Y
Pu
Pu
Pu
Pu
Pu
Bromphenol blue
Y
Y
B
B
B
B
B
B
B
B
B
Methyl Orange
P
P
P
O
O
O
O
O
O
O
O
1
9
10 11 12
If a solution has a [H+] = 4.2x10-4, what color would it be in methyl orange?
pink
98-100. Know how the qualitative analysis lab worked. What colors are the flame tests? What
does the brown ring test for? How do we test for ammonium? Which chemical were
poisonous to the environment?