Chemistry for Changing Times 12th edition

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John W. Hill, Doris K. Kolb and Terry W. McCreary
Publisher: Pearson Education


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  • Chapter 1: Chemistry
    • 1.1: Risk Benefit Analysis
    • 1.2: Mass and Weight
    • 1.3: Length, Area, and Volume
    • 1.4: Physical and Chemical Properties and Change
    • 1.5: Substances and Mixtures (1)
    • 1.6: Elements and Compounds (1)
    • 1.7: The Metric System: Measurement and Unit Conversion (1)
    • 1.8: Density
    • 1.9: Energy: Heat and Temperature
    • 1: Review Questions
    • 1: Additional Problems (1)
    • 1: Extra Problems (2)
    • WebAssign Answer Entry Tutorials (1)

  • Chapter 2: Atoms
    • 2.1: Conservation of Mass (2)
    • 2.2: Definite Proportions (2)
    • 2.3: Multiple Proportions
    • 2.4: Dalton's Atomic Theory (1)
    • 2.5: Chemical Compounds
    • 2: Review Questions
    • 2: Additional Problems (1)
    • 2: Extra Problems
    • WebAssign Answer Entry Tutorials

  • Chapter 3: Atomic Structure
    • 3.1: Nuclear Symbols and Isotopes
    • 3.2: Quantum Mechanical Notation for Electron Structure
    • 3: Review Questions
    • 3: Additional Problems
    • 3: Extra Problems (13)
    • WebAssign Answer Entry Tutorials (1)

  • Chapter 4: Chemical Bonds
    • 4.1: Lewis Symbols for Elements
    • 4.2: Lewis Structures for Ionic Compounds
    • 4.3: Names and Symbols for Simple Ions
    • 4.4: Names and Formulas for Binary Ionic Compounds
    • 4.5: Names and Formulas for Ionic Compounds with Polyatomic Ions
    • 4.6: Molecules: Covalent Bonds
    • 4.7: Names and Formulas for Covalent Compounds (2)
    • 4.8: Lewis Formulas for Covalent Compounds
    • 4.9: Electronegativity: Polar Covalent Bonds
    • 4.10: Classifying Bonds
    • 4.11: VSEPR Theory: The Shapes of Molecules (1)
    • 4.12: Polar and Nonpolar Molecules
    • 4.13: Molecules That Are Exceptions to the Octet Rule
    • 4: Review Questions
    • 4: Additional Problems
    • 4: Extra Problems (5)
    • WebAssign Answer Entry Tutorials

  • Chapter 5: Chemical Accounting
    • 5.1: Interpreting Formula Units (1)
    • 5.2: Interpreting Chemical Equations
    • 5.3: Balancing Chemical Equations
    • 5.4: Volume Relationships in Chemical Equations (1)
    • 5.5: Avogadro's Number
    • 5.6: Formula Masses and Molar Masses (2)
    • 5.7: Mole and Mass Relationships in Chemical Equations (2)
    • 5.8: Molarity of Solutions (3)
    • 5.9: Percent Concentrations of Solutions
    • 5: Review Questions
    • 5: Additional Problems
    • 5: Extra Problems (5)
    • WebAssign Answer Entry Tutorials

  • Chapter 6: Gases, Liquids, Solids, and Inter-Molecular Forces
    • 6.1: Intermolecular Forces
    • 6.2: Boyle's Law
    • 6.3: Charles's Law
    • 6.4: Molar Volume and Gas Densities
    • 6.5: The Ideal Gas Law
    • 6: Review Questions
    • 6: Additional Problems
    • 6: Extra Problems
    • WebAssign Answer Entry Tutorials

  • Chapter 7: Acids and Bases
    • 7.1: Acids and Bases: The Arrhenius Theory
    • 7.2: Acids and Bases: The Bronsted-Lowry Acid-Base Theory (2)
    • 7.3: Acids and Bases: Names and Formulas
    • 7.4: Acidic and Basic Anhydrides (2)
    • 7.5: Strong and Weak Acids and Bases (2)
    • 7.6: Ionization of Acids and Bases (1)
    • 7.7: Neutralization (3)
    • 7.8: The pH Scale (3)
    • 7.9: Buffers and Conjugate Acid-Base Pairs
    • 7.10: Antacids
    • 7: Review Questions
    • 7: Additional Problems
    • 7: Extra Problems
    • WebAssign Answer Entry Tutorials

  • Chapter 8: Oxidation and Reduction
    • 8.1: Recognizing Oxidation and Reduction (1)
    • 8.2: Oxidizing Agents and Reducing Agents (2)
    • 8.3: Half-Reactions (2)
    • 8.4: Oxidation and Reduction: Chemical Reactions (5)
    • 8.5: Combination with Oxygen (1)
    • 8: Review Questions
    • 8: Additional Problems
    • 8: Extra Problems
    • WebAssign Answer Entry Tutorials

  • Chapter 9: Organic Chemistry
    • 9.1: Organic and Inorganic (1)
    • 9.2: Names and Formulas of Hydrocarbons (1)
    • 9.3: Names and Formulas: Alcohols and Phenols
    • 9.4: Names and Formulas: Ethers
    • 9.5: Names and Formulas: Aldehydes and Ketones
    • 9.6: Names and Formulas: Carboxylic Acids
    • 9.7: Names and Formulas: Esters
    • 9.8: Names and Formulas: Nitrogen-Containing Compounds
    • 9.9: Isomers and Homologs (1)
    • 9.10: Classification of Hydrocarbons (1)
    • 9.11: Functional Groups
    • 9: Review Questions
    • 9: Additional Problems
    • 9: Extra Problems (2)
    • WebAssign Answer Entry Tutorials

  • Chapter 10: Polymers
    • 10.1: Polyethylene
    • 10.2: Addition Polymerization (2)
    • 10.3: Rubber and Other Elastomers
    • 10.4: Condensation Polymerization (1)
    • 10.5: Properties of Polymers
    • 10: Review Questions
    • 10: Additional Problems
    • 10: Extra Problems
    • WebAssign Answer Entry Tutorials (1)

  • Chapter 11: Nuclear Chemistry
    • 11.1: Nuclear Equations (2)
    • 11.2: Half-Life (1)
    • 11.3: Radioisotopic Dating (1)
    • 11: Review Questions
    • 11: Additional Problems
    • 11: Extra Problems (2)
    • WebAssign Answer Entry Tutorials

  • Chapter 12: Chemistry of the Earth
    • 12.1: Composition of Earth
    • 12.2: Silicate Minerals
    • 12.3: Modified Silicates
    • 12.4: Metals and Ores (1)
    • 12.5: Oxidation and Reduction
    • 12.6: Mass Relationships (1)
    • 12: Review Questions
    • 12: Additional Problems
    • 12: Extra Problems (4)
    • WebAssign Answer Entry Tutorials

  • Chapter 13: Air
    • 13.1: The Atmosphere: Composition and Cycles
    • 13.2: Industrial Smog (4)
    • 13.3: Photochemical Smog (2)
    • 13.4: Carbon Monoxide (2)
    • 13.5: The Ozone Layer
    • 13.6: Acid Rain (1)
    • 13.7: Indoor Air Pollution (1)
    • 13.8: Carbon Dioxide and Climate
    • 13: Review Questions
    • 13: Additional Problems
    • 13: Extra Problems (2)
    • WebAssign Answer Entry Tutorials

  • Chapter 14: Water
    • 14.1: Properties of Water (2)
    • 14.2: Natural Waters
    • 14.3: Acidic Waters (1)
    • 14.4: Municipal Water Supplies
    • 14.5: Wastewater Treatment
    • 14.6: Chemical Equations (1)
    • 14.7: Parts per Million and Parts per Billion (1)
    • 14: Review Questions
    • 14: Additional Problems
    • 14: Extra Problems (2)
    • WebAssign Answer Entry Tutorials

  • Chapter 15: Energy
    • 15.1: Fuels and Combustion (3)
    • 15.2: Energy and Chemical Reactions (1)
    • 15.3: Energy and the Laws of Thermodynamics
    • 15.4: Fossil Fuels
    • 15.5: Natural Gas
    • 15.6: Petroleum
    • 15.7: Nuclear Power
    • 15.8: Renewable Energy Sources
    • 15.9: Synthetic and Converted Fuels
    • 15: Review Questions
    • 15: Additional Problems
    • 15: Extra Problems (4)
    • WebAssign Answer Entry Tutorials

  • Chapter 16: Biochemistry
    • 16.1: Carbohydrates (1)
    • 16.2: Lipids: Fats and Oils (1)
    • 16.3: Proteins
    • 16.4: Nucleic Acids: Parts and Structure (2)
    • 16.5: DNA: Self-Replication
    • 16.6: RNA: Protein Synthesis and the Genetic Code (2)
    • 16: Review Questions
    • 16: Additional Problems
    • 16: Extra Problems (1)
    • WebAssign Answer Entry Tutorials

  • Chapter 17: Food
    • 17.1: Carbohydrates
    • 17.2: Fats and Cholesterol
    • 17.3: Proteins (1)
    • 17.4: Minerals
    • 17.5: Vitamins (1)
    • 17.6: Food Additives
    • 17.7: Calorie and Nutrient Calculations (1)
    • 17: Review Questions
    • 17: Additional Problems
    • 17: Extra Problems (5)
    • WebAssign Answer Entry Tutorials

  • Chapter 18: Drugs
    • 18.1: NSAIDs and Related Drugs
    • 18.2: Antibacterial Drugs
    • 18.3: Antiviral Drugs
    • 18.4: Anticancer Drugs
    • 18.5: Hormones and Birth Control Drugs
    • 18.6: Drugs and the Mind
    • 18.7: Anesthetics
    • 18.8: Narcotics (1)
    • 18: Review Questions (4)
    • 18: Additional Problems
    • 18: Extra Problems (4)
    • WebAssign Answer Entry Tutorials

  • Chapter 19: Fitness and Health
    • 19: Problems (5)
    • 19: Review Questions
    • 19: Additional Problems
    • 19: Extra Problems (1)
    • 19: WebAssign Answer Entry Tutorials

  • Chapter 20: Chemistry Down on the Farm...
    • 20: Problems
    • 20: Review Questions
    • 20: Additional Problems
    • 20: Extra Problems
    • 20: WebAssign Answer Entry Tutorials

  • Chapter 21: Househould Chemicals
    • 21: Problems (2)
    • 21: Review Questions (1)
    • 21: Additional Problems
    • 21: Extra Problems (4)
    • 21: WebAssign Answer Entry Tutorials

  • Chapter 22: Poisons
    • 22: Problems (9)
    • 22: Review Questions (1)
    • 22: Additional Problems
    • 22: Extra Problems (1)
    • 22: WebAssign Answer Entry Tutorials

Questions Available within WebAssign

Most questions from this textbook are available in WebAssign. The online questions are identical to the textbook questions except for minor wording changes necessary for Web use. Whenever possible, variables, numbers, or words have been randomized so that each student receives a unique version of the question. This list is updated nightly.

Question Group Key
AP - Additional Problems
P - Problems
RQ - Review Questions
XP - Extra Problems


Question Availability Color Key
BLACK questions are available now
GRAY questions are under development


Group Quantity Questions
Chapter 1: Chemistry
1.AP 1 071
1.P 3 033 040 052
1.T 1 001
1.XP 2 001 002
Chapter 2: Atoms
2.AP 1 046
2.P 5 020 021 026 027 036
Chapter 3: Atomic Structure
3.T 1 001
3.XP 13 001 002 003 004 005 006 007 008 009 010 011 012 013
Chapter 4: Chemical Bonds
4.P 3 031 033 049
4.XP 5 001 002 003 004 005
Chapter 5: Chemical Accounting
5.P 9 007 020 030 032 034 036 040 042 044
5.XP 5 001 002 003 004 005
Chapter 6: Gases, Liquids, Solids, and Inter-Molecular Forces
6 0  
Chapter 7: Acids and Bases
7.P 13 018 021 029 030 032 034 041 043 044 046 048 049 051
Chapter 8: Oxidation and Reduction
8.P 11 014 017 018 024 026 027 030 031 033 036 038
Chapter 9: Organic Chemistry
9.P 4 016 023 041 046
9.XP 2 001 002
Chapter 10: Polymers
10.P 3 015 020 028
10.T 1 001
Chapter 11: Nuclear Chemistry
11.P 4 022 027 034 040
11.XP 2 001 002
Chapter 12: Chemistry of the Earth
12.P 2 030 040
12.XP 4 001 002 003 004
Chapter 13: Air
13.P 10 016 018 020 022 025 028 030 032 039 042
13.XP 2 001 002
Chapter 14: Water
14.P 5 010 014 022 038 040
14.XP 2 001 002
Chapter 15: Energy
15.P 4 005 010 012 018
15.XP 4 001 002 003 004
Chapter 16: Biochemistry
16.P 6 022 036 054 056 064 066
16.XP 1 001
Chapter 17: Food
17.P 3 025 039 050
17.XP 5 001 002 003 004 005
Chapter 18: Drugs
18.P 1 037
18.RQ 4 002 004 009 014
18.XP 4 001 002 003 004
Chapter 19: Fitness and Health
19.P 5 026 030 034 040 051
19.XP 1 001
Chapter 20: Chemistry Down on the Farm...
20 0  
Chapter 21: Househould Chemicals
21.P 2 042 059
21.RQ 1 007
21.XP 4 001 002 003 004
Chapter 22: Poisons
22.P 9 012 014 015 019 021 023 027 036 038
22.RQ 1 001
22.XP 1 001
Total 170