Chemistry in the Community FINAL EXAM REVIEW

UNIT 1: Water: Exploring Solutions

Section A – Sources and Uses of Water

1. In the foul water lab, what was the purpose of the following items?

a. sand

b. gravel

c. charcoal

d. pipette

2. What is filtration?

3. What is distillation?

4. Explain the purpose of the blinkie demonstration.

5. What instrument is most precise in measuring a volume of water, a beaker, a pipette, or a graduated cylinder? Explain how to take this reading.

6. List 5 examples in your home where water is wasted.

7. List 5 ways to conserve water.

8. What is the hydrologic cycle. Explain each step.

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Section B – Looking at Water and its Contaminants

9. What compound has a density of 1 g/mL?

10. If a compound has a density less than 1 g/mL, what does that tell you about the compound?

a. If the density is greater than 1 g/mL, what does that tell you about the compound?

11. Define and provide examples of the following vocabulary:

a. solution

b. suspension

c. colloid

12. Give an atom inventory for the following:

a. H2SO4

b. NaBr

c. Al2(SO4)3

13. Define the following:

a. Chemical property

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b. Chemical change

c. Physical property

d. Physical change

14. Define and provide examples for the following:

a. atom

b. ion

c. isotope

d. compound

15. Name the or write the symbols for the following ionic compounds

a. NaCl b. potassium iodide

c. MgBr2 d. aluminum oxide

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Section C – Investigating the Cause of the Fishkill

1. Definitions

a. Saturated

b. Unsaturated

c. Supersaturated

d. Solute

e. Solvent

f. Polar

g. Nonpolar

h. Soluble

i. Insoluble

j. Likes Dissolve Likes

2. In a mixture composed of 100 grams of water and 25 grams of KCl,

a. What is the solute?

b. What is the solvent?

c. At 40°C, is this solution saturated, unsaturated with __ g still can fit, or saturated with __ g undissolved? Show work.

d. List three ways to make more salt dissolve at this temperature.

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3. Describe the process for the ionic compound KCl dissolving in water.

(a) Step One

(b) Step Two

(c) Step Three

5. Why doesn’t oil dissolve in water? Be specific.

PROBLEMS

USE THE GRAPH TO ANSWER ALL SOLUBILITY QUESTIONS.

1. What is the solubility in 100 mL water of KNO3 at 40°C?

2. How many grams of KCl will dissolve in 200.0 grams of water at 40’C?

3. How many grams of KNO3 can dissolve in 50.0 g of water at 40°C?

4. Describe a solution in which 50 g of KNO3 are dissolved in 100 mL ofwater at 40°C.

5. Describe a solution in which 80 g of KNO3 are dissolved in 100 g of water at 40°C.

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6. What is the percent by mass of a solution containing 20.0 g of MgCl 2 in 85.0 mL of water?

7. What is the PPM of a solution consisting of 325 mg of gold ions in 750.0 mL of water?

8. What mass of solute is needed to make a 30.0% MgCl2 solution containing 845 grams of solution?

9. What mass of solute is needed to make a 35% MgCl2 solution containing 3.95 L of water?

Section D – Water Purification and Treatment

16. List and describe the steps involved in the water treatment process. Include all optional treatments as well.

17. What is algal growth and how can it be prevented?

18. What is a precipitate and how is it formed?

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UNIT 2: Materials: Structure and Uses

Section A – Why We Use What We Do

Vocab.

Physical Property –

Physical Change –

Chemical Property –

Chemical Change –

Combustion –

Metal –

Nonmetal –

Metalloid –

Atomic Number –

Mass Number –

Isotope –

Atomic Weight –

Group –

Period –

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1. How are elements with similar properties arranged within the Periodic Table?

2. The modern Periodic Table classifies elements according to ____________________.

3. Identify each of the following as a Physical (P) or a Chemical (C) property:

_____ a. The hardness of diamonds enables them to be used in drill bits.

_____ b. Silver utensils should not be used to handle sulfur-containing foods, since silver will tarnish upon contact.

_____ c. Iron will corrode and rust when exposed to moist air.

_____ d. The high melting point of tungsten makes it useful in light bulb filaments.

_____ e. Metals are ductile

4. Identify the following as a Metal (M), nonmetal (NM) or Metalloid (ML)

_____ a. Found along the “staircase” on the Periodic Table

_____ b. Found on the left of the Periodic Table

_____ c. Dull and non-conductive

_____ d. Si

_____ e. Calcium

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5. Circle the word that best completes the sentence.

a) The boiling point of elements (increases then decreases or decreases then increases) across a period from left to right.

b) The most metallic elements are located to the (left or right) of the periodic table.

c) The atomic radius of elements (increases or decreases) across a period from left to right.

d) The most reactive nonmetals are located to the (left or right) of the periodic table.

e) The electronegativity of elements (increases or decreases) across a period.

6. Complete the following table:

Name Symbol At. # Mass # Protons Neutrons ElectronsGold

K

86

122

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7. Give the location of the following elements by period and group number.

a. Calcium: period ________ group ________

b. Nitrogen: period ________ group ________

c. Hydrogen: period ________ group ________

d. Antimony: period ________ group ________

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Section B – Earth’s Mineral Resources

Vocab :

Ore –

Lithosphere –

Mineral –

Activity Series –

Oxidation –

Reduction –

Oxidizing Agent –

Reducing Agent –

1. The three methods of metal purification are ________________, ______________ and _______________________.

2. A metal is usually obtained from its ore by a process called ___________________.

3. In the reaction: Cu(s) + Ag+1(aq) Cu+2(aq) + 2Ag(s), which atom or ion was oxidized? Which is the oxidizing agent?

4. In the reaction: Cu+2(aq) + Mg(s) Mg+2(aq) + Cu(s), which atom or ion was reduced? Which is the reducing agent?

5. Which is more active? a. Calcium or Chromium

b. Manganese or Sodium

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Complete the following chart:Element Atomic # Mass # # of p+ # of e- # of no Atom,

ion, or isotope?

C

Ne

Mn

Mg

Mg+2

Y

U - 236

Section C – Conserving Matter and Section D – Materials: Designing for Desired Properties

1. Balance the following equation.

___ Zn + ___ CuSO4 ___ Cu + ___ ZnSO4

2. ___ A1 + ___ ZnC12 ___ A1C13 + ___ Zn

3. Chemical equations are balanced with numbers called: A) Subscripts B) Atoms C) Coefficients D) Exponents

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4. The _____ are on the left side of a chemical equation and the ____ are on the right side.A) Coefficients and subscriptsB) Reactants and productsC) Atoms and compoundsD) Chemicals and products

5. The processing of used manufactured materials to produce new manufactured items is called A) Recycling B) ReusingC) SmeltingD) Galvanizing

6. It requires the least amount of energy if we easily obtain aluminum from: A) Aluminum Oxide Ore B) Bauxite C) ClayD) Scrap Aluminum

7. Chemists use the term mole, which is most similar in use to which of these units? A) GallonB) Degree C) Dozen D) Ton

8. Use the following to answer the following:

2Cr2O3 + 3Si 4Cr + SiO3

According to the equation, what is the total number of moles of Silicon used? A) OneB) TwoC) ThreeD) Four

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9. Given the balanced equation:

H2SO4 + 2KOH 2KCl + H2O

If 226.0 grams of potassium hydroxide completely reacts with reacts with H2SO4, what is the total mass of water that is produced?

10. Given the balanced equation:

2KClO3 2 KCl + 3O2

What is the total mass of the products in this equation?A) 245 gB) 123 gC) 336 gD) 368 g

11. In a chemical equation, the atom count for each element on the reactant side must be _________ to the atom count for each element on the product side.A) Equal toB) More thanC) Less than

12. Law of _____________ states that the total number of atoms on the reactants must equal the total number of atoms on the products A) Kinetic EnergyB) Conservation of Matter C) Partial PressuresD) Multiple Proportions

13. Calculate the molar mass of the compound: (NH4)2Cr2O7

A) 234.1 grams per moleB) 236.1 grams per moleC) 252.1 grams per moleD) 268.1 grams per mole

14. Calculate the percent by mass of copper in the compound, Cu(OH)2.A) 66.0 %

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B) 89.0 %C) 91.1 %D) 101.3 %

15. After 1982, the element that comprises pennies the most (97.5%) are made with A) Copper B) Iron C) Aluminum D) Zinc E) Lead

16. Which choice is a renewable resource? A) Petroleum B) Natural GasC) WoodD) Metals

17. The type of plant that produces electricity by burning more than 300 million tons of solid waste is calledA) Oil refineries B) Nuclear Waste GeneratorsC) Waste-to-Energy plantsD) Recycling Plants

18. A material that has almost no resistance to the flow of electricity is called a(n) _________________.A) SemiconductorB) CoatingC) Thin FilmD) Superconductor

19. Which element cannot be electroplated on the surface of a sheet of brass?A) SilverB) PhosphorusC) GoldD) Chromium

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20. Diamond, graphite, and coal are all allotropes of which element?A) aluminumB) SulfurC) platinumD) Carbon

21. Buckminsterfullerene is a substance with round molecules made of 60 atoms that are all the elementA) CopperB) CarbonC) IronD) Mercury

22. An element that is a semiconductor isA) SilverB) SodiumC) SiliconD) Manganese

Unit 3: Petroleum: Breaking and Making Bonds

Section A – Petroleum: What is it?

Vocab:

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a. Crude Oil -

b. Hydrocarbon -

c. Fraction -

d. Fractional Distillation -

e. Intermolecular Forces -

f. Energy Level -

g. Organic Chemistry -

h. Valence Electrons -

i. Valence Shell -

j. Covalent Bond –

1. Complete the following table:

Element name Energy Levels # of Valence ElectronsFluorineCarbonSiliconMagnesiumNeon

2. Draw the electron dot diagram for the following:

a) Argon b) Phosphorus

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c) Magnesium ion d) Fluorine ion

3. Draw the structural formula for the following:

a) methane b) water

c) carbon dioxide d) propene

4. Fractional distillation is based on the fact that substances found in crude oil have different _________________________.

5. Hydrocarbon boiling points _______________________ as the number of C atoms per molecule increases

6. Based on the length of the carbon chain, which of the following would have the HIGHEST boiling point; C7H14, C3H8 or C5H12?

7. The fourteenth member of the alkane family has the formula _________________

Section B – Petroleum: An Energy Source

1. What is the difference between potential and kinetic energy?

2. Chemical energy is a form of ____________________ energy.

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3. Classify each of the following as an example of kinetic or potential energy:a. A boulder perched at the top of a hill ____________

b. A train traveling down the tracks ____________

c. A tank of gasoline ____________

d. Water flowing down a river ____________

4. Consider the following equation:

2 C2H2 + 5 O2 4 CO2 + 2 H2O + 2512 kJ

Is this reaction endothermic or exothermic? How do you know?

5. In an exothermic reaction which has more energy, the reactants or the products? Explain.

6. Write the chemical reaction for the combustion of heptane.

7. Define specific heat.

8. How much energy is needed to raise the temp of 125 g sample of liquid water from 50 degrees Celsius to 135 degrees Celsius? (Cp = 4.2 J/g)

9. A 68 g sample of liquid water was heated from 55 degrees Celsius to 95 degrees Celsius. How much heat was gained by the water during this process? (Cp = 4.2 J/g)

9. When a chemical reaction occurs, energy is __________________ when bonds break, and ____________________ when new chemical bonds form.

Section C – Petroleum: A Building Material Source and Section D – Energy Alternatives to Petroleum

1. Draw the structure of the following compounds:

a) Pentane c) pentyne

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b) pentene

Label each of the above as an alkane, alkene or alkyne.

2. Define the following:

a) Biomolecules –

b) Biodiesel –

3. Complete the following chart:

Power Options

Fuel Type How it Works

Compressed Natural Gas

Fuel Cells

Hybrid Gasoline-Electric

Unit 4: Air: Chemistry and the Atmosphere

Secation A – Gases in the Atmosphere

Fill in the blanks.

1. The atmosphere is composed of 78% _____________ and 21% _____________.

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2. The ____________________ is a thin layer within 10-15 km of the earth's

surface.

3. As altitude increases, air pressure ________________.

4. Standard temperature is _______________K or ____________ºC.

5. Standard pressure is _____________mm Hg or _____________atm.

6. If pressure is lowered and the temperature and number of moles are constant, the

volume will ______________.

7. If temperature is raised and the volume and number of moles are constant the

pressure will _________________.

8. The gas laws do not predict gas behavior well when the _____________________

is very high or the _____________________ is very low.

9. What causes a gas in a closed container to exert pressure?

10. The four assumptions of the Kinetic Molecular Theory of Gases are

1. Gases are ___________ ______________ (molecules) whose size is negligible.

2. Gas molecules are in constant random _________________.

3. Molecular collisions are __________________.

4. As the ______________________ of a gas increase, its kinetic energy increases.

11. Convert −45ºC to Kelvin.

12. Convert 1.2 moles NH3 to mass.

13. Convert 88 g H2S to moles.

14. Given the following reaction for burning gasoline:

2 C8H18 (g) + 25 O2 (g) → 16 CO2 (g) + 18 H2O (g)

How many liters of O2 are necessary to react with 5 liters of C8H18?

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15. Determine the pressure exerted by 0.25 mole neon gas in a 2.75 L container at 35ºC.

16. What volume would 10.0 g of gaseous CO2 occupy at STP?

17. A gas in a balloon at 1000 mm Hg occupies 1500 mL. At what pressure will the gas occupy 3000 mL if the temperature remains unchanged?

18. A 4 L sample of hydrogen is collected at 800.0 mm Hg and 30.0ºC. What volume will the gas occupy at STP?

Section B – Radiation and Climate

1. Definitions

a. Electromagnetic Radiation

b. Electromagnetic Spectrum

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c. Photons

d. Frequency

e. Wavelength

f. Infrared Radiation

g. Visible Radiation

h. Ultraviolet Radiation

i. Reflectivity

j. Specific Heat

k. Greenhouse Gases

l. Greenhouse Effect

m. Spiraling Effect

n. Runaway Greenhouse Effect

o. The Carbon Cycle

2. What is the source of Earth's energy? What is the source of the Sun's energy?

3. Complete the following table:

Radiation Type Ultraviolet A Ultraviolet B Ultraviolet C Infrared Visible

Frequency X X X X

Wavelength X X

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Energy X X

Portion to Reach Earth

Effect on Earth

X X

4. What is the relationship between frequency and wavelength?

5. What is the relationship between frequency and energy?

6. What is the relationship between wavelength and energy?

8. What happens to the 70% of the Sun's solar energy that does not reach the Earth's surface?

9. What is the relationship between amount of heat reflected, absorbed and color?

10. What is the relationship between specific heat and how much heat is needed to change the temperature of an object?

11. What is the function of the ozone layer?

12. List three examples of greenhouse gases.

Section C – Acids in the Atmosphere

1. __________ __________ is fog, sleet or snow with pH lower than 5.6

2. Four natural sources of acidity in rain are CO2 in the atmosphere, ________________,

__________________________, and _____________________.

3. The major components of acid rain are ________________, ____________________,

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and __________________.

4. Coal burning power plants are major contributors of _______________ from the

burning of high sulfur coal.

5. ________________________ contributes 56% of NOx emissions and _____________

________________ contribute 37 % of NOx emissions.

6. Identify the following as acidic, basic, or neutral

a. _____H3PO4 b. _____CaCl2 c._____Ca(OH)2 d. _____ C2H6

7. Complete the following table:

Substance pH [H3O+] Acid, Base, or Neutral?

Vinegar 3

Milk 1.00 x 10-6 M

Pure water

Coffee 4

Rainwater 2.51 x 10-6 M

Ammonia 1.21 x 10-11M

8. Which of the following is a neutralization reaction?

a. C3H8 + 5 O2 → 3 CO2 + 4 H2O

b. HCl + NaOH → NaCl + H2O

c. HCl + H2O → H3O+ + Cl−

c. MgO + H2O → Mg(OH)2

9. Identify the following as a strong acid, a weak acid, a strong base, a weak base or neutral.

_____ 1 M HCl with pH = 0.1 _____ pure water with pH = 7.0

_____ saliva with pH = 6.7 _____ 0.1 N NaOH with pH = 14.0

_____ eggs with pH = 7.8

Section D – Air Pollution: Sources, Effects and Solutions

Fill in the blanks. Some answers may be used more than once.

Air conditioners Filter Sulfur dioxideCarbon monoxide Nitrogen dioxide TransportationCatalytic converter Ozone Wet scrubberChlorine Photochemical smog

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Electrostatic precipitator Refrigerators

1. The main source of air pollution in the United States is ____________________.

2. The major pollutant from cars is ________________________. This is a deadly

gas that is given off due to incomplete combustion. It is important not to idle a

car in a closed garage due to this gas. It can also be given off in a home by a

faulty furnace.

3. The Air Quality Index (AQI) measures these four pollutants: _______________,

_________________, _________________ and _________________.

4. Two harmful components of __________________________________ are

NO2 and O3 (ozone). _______________ can inhibit plant growth. ___________

is a powerful oxidizing agent that can crack rubber, corrode metals and damage

plant and animal tissues.

5. A very thin layer of ______________ in the stratosphere protects the earth by

absorbing UV radiation.

6. Chlorofluorocarbons deplete the ozone layer because they supply ____________

radicals to the atmosphere. Because of their destruction of the ozone layer, CFC's

are no longer produced in over 170 countries in the world. CFC's were once

widely used for _________________________ and _______________________.

7. Three ways to reduce particulate pollution is with ________________________,

_____________________, and ____________________.

8. A ________________ _______________ reduces the amount of NOx and CO

emissions from a car.

9. Ozone can be both harmful and helpful to humans. Tropospheric or "ground-

level" ozone is harmful while stratospheric ozone is helpful. Explain.

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