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1. Intro to General Chemistry(0)

Classification of Matter
(0)

Physical & Chemical Changes
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Chemical Properties
(0)

Physical Properties
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Intensive vs. Extensive Properties
(0)

Temperature
(0)

Scientific Notation
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SI Units
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Metric Prefixes
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Significant Figures
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Significant Figures: Precision in Measurements
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Significant Figures: In Calculations
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Conversion Factors
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Dimensional Analysis
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Density
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Density of Geometric Objects
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Density of Non-Geometric Objects
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2. Atoms & Elements(0)

The Atom
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Subatomic Particles
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Isotopes
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Ions
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Atomic Mass
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Periodic Table: Classifications
(0)

Periodic Table: Group Names
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Periodic Table: Representative Elements & Transition Metals
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Periodic Table: Element Symbols
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Periodic Table: Elemental Forms
(0)

Periodic Table: Phases
(0)

Periodic Table: Charges
(0)

Calculating Molar Mass
(0)

Mole Concept
(0)

Law of Conservation of Mass
(0)

Law of Definite Proportions
(0)

Atomic Theory
(0)

Law of Multiple Proportions
(0)

Millikan Oil Drop Experiment
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Rutherford Gold Foil Experiment
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3. Chemical Reactions(0)

Empirical Formula
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Molecular Formula
(0)

Combustion Analysis
(0)

Combustion Apparatus
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Polyatomic Ions
(0)

Naming Ionic Compounds
(0)

Writing Ionic Compounds
(0)

Naming Ionic Hydrates
(0)

Naming Acids
(0)

Naming Molecular Compounds
(0)

Balancing Chemical Equations
(0)

Stoichiometry
(0)

Limiting Reagent
(0)

Percent Yield
(0)

Mass Percent
(0)

Functional Groups in Chemistry
(0)

4. BONUS: Lab Techniques and Procedures(0)

Laboratory Materials
(0)

Experimental Error
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Distillation & Floatation
(0)

Chromatography
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Filtration and Evaporation
(0)

Extraction
(0)

Test for Ions and Gases
(0)

5. BONUS: Mathematical Operations and Functions(0)

Multiplication and Division Operations
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Addition and Subtraction Operations
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Power and Root Functions -
(0)

Logarithmic Functions
(0)

The Quadratic Formula
(0)

6. Chemical Quantities & Aqueous Reactions(0)

Solutions
(0)

Molarity
(0)

Osmolarity
(0)

Dilutions
(0)

Solubility Rules
(0)

Electrolytes
(0)

Molecular Equations
(0)

Gas Evolution Equations
(0)

Solution Stoichiometry
(0)

Complete Ionic Equations
(0)

Calculate Oxidation Numbers
(0)

Redox Reactions
(0)

Balancing Redox Reactions: Acidic Solutions
(0)

Balancing Redox Reactions: Basic Solutions
(0)

Activity Series
(0)

7. Gases(0)

Pressure Units
(0)

The Ideal Gas Law
(0)

The Ideal Gas Law Derivations
(0)

The Ideal Gas Law Applications
(0)

Chemistry Gas Laws
(0)

Chemistry Gas Laws: Combined Gas Law
(0)

Mole Fraction of Gases
(0)

Partial Pressure
(0)

The Ideal Gas Law: Molar Mass
(0)

The Ideal Gas Law: Density
(0)

Gas Stoichiometry
(0)

Standard Temperature and Pressure
(0)

Effusion
(0)

Root Mean Square Speed
(0)

Kinetic Energy of Gases
(0)

Maxwell-Boltzmann Distribution
(0)

Velocity Distributions
(0)

Kinetic Molecular Theory
(0)

Van der Waals Equation
(0)

8. Thermochemistry(0)

Nature of Energy
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Kinetic & Potential Energy
(0)

First Law of Thermodynamics
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Internal Energy
(0)

Endothermic & Exothermic Reactions
(0)

Heat Capacity
(0)

Constant-Pressure Calorimetry
(0)

Constant-Volume Calorimetry
(0)

Thermal Equilibrium
(0)

Thermochemical Equations
(0)

Formation Equations
(0)

Enthalpy of Formation
(0)

Hess's Law
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9. Quantum Mechanics(0)

Wavelength and Frequency
(0)

Speed of Light
(0)

The Energy of Light
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Electromagnetic Spectrum
(0)

Photoelectric Effect
(0)

De Broglie Wavelength
(0)

Heisenberg Uncertainty Principle
(0)

Bohr Model
(0)

Emission Spectrum
(0)

Bohr Equation
(0)

Introduction to Quantum Mechanics
(0)

Quantum Numbers: Principal Quantum Number
(0)

Quantum Numbers: Angular Momentum Quantum Number
(0)

Quantum Numbers: Magnetic Quantum Number
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Quantum Numbers: Spin Quantum Number
(0)

Quantum Numbers: Number of Electrons
(0)

Quantum Numbers: Nodes
(0)

10. Periodic Properties of the Elements(0)

The Electron Configuration
(0)

The Electron Configuration: Condensed
(0)

The Electron Configurations: Exceptions
(0)

The Electron Configuration: Ions
(0)

Paramagnetism and Diamagnetism
(0)

The Electron Configuration: Quantum Numbers
(0)

Valence Electrons of Elements
(0)

Periodic Trend: Metallic Character
(0)

Periodic Trend: Atomic Radius
(0)

Periodic Trend: Ionic Radius
(0)

Periodic Trend: Ionization Energy
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Periodic Trend: Successive Ionization Energies
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Periodic Trend: Electron Affinity
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Periodic Trend: Electronegativity
(0)

Periodic Trend: Effective Nuclear Charge
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Periodic Trend: Cumulative
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11. Bonding & Molecular Structure(0)

Lewis Dot Symbols
(0)

Chemical Bonds
(0)

Dipole Moment
(0)

Octet Rule
(0)

Formal Charge
(0)

Lewis Dot Structures: Neutral Compounds
(0)

Lewis Dot Structures: Sigma & Pi Bonds
(0)

Lewis Dot Structures: Ions
(0)

Lewis Dot Structures: Exceptions
(0)

Lewis Dot Structures: Acids
(0)

Resonance Structures
(0)

Average Bond Order
(0)

Bond Energy
(0)

Coulomb's Law
(0)

Lattice Energy
(0)

Born Haber Cycle
(0)

12. Molecular Shapes & Valence Bond Theory(0)

Valence Shell Electron Pair Repulsion Theory
(0)

Equatorial and Axial Positions
(0)

Electron Geometry
(0)

Molecular Geometry
(0)

Bond Angles
(0)

Hybridization
(0)

Molecular Orbital Theory
(0)

MO Theory: Homonuclear Diatomic Molecules
(0)

MO Theory: Heteronuclear Diatomic Molecules
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MO Theory: Bond Order
(0)

13. Liquids, Solids & Intermolecular Forces(0)

Molecular Polarity
(0)

Intermolecular Forces
(0)

Intermolecular Forces and Physical Properties
(0)

Clausius-Clapeyron Equation
(0)

Phase Diagrams
(0)

Heating and Cooling Curves
(0)

Atomic, Ionic, and Molecular Solids
(0)

Crystalline Solids
(0)

Simple Cubic Unit Cell
(0)

Body Centered Cubic Unit Cell
(0)

Face Centered Cubic Unit Cell
(0)

14. Solutions(0)

Solutions: Solubility and Intermolecular Forces
(0)

Molality
(0)

Parts per Million (ppm)
(0)

Mole Fraction of Solutions
(0)

Solutions: Mass Percent
(0)

Types of Aqueous Solutions
(0)

Intro to Henry's Law
(0)

Henry's Law Calculations
(0)

The Colligative Properties
(0)

Boiling Point Elevation
(0)

Freezing Point Depression
(0)

Osmosis
(0)

Osmotic Pressure
(0)

Vapor Pressure Lowering (Raoult's Law)
(0)

15. Chemical Kinetics(0)

Intro to Chemical Kinetics
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Energy Diagrams
(0)

Catalyst
(0)

Factors Influencing Rates
(0)

Average Rate of Reaction
(0)

Stoichiometric Rate Calculations
(0)

Instantaneous Rate
(0)

Collision Theory
(0)

Arrhenius Equation
(0)

Rate Law
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Reaction Mechanism
(0)

Integrated Rate Law
(0)

Half-Life
(0)

16. Chemical Equilibrium(0)

Intro to Chemical Equilibrium
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Equilibrium Constant K
(0)

Equilibrium Constant Calculations
(0)

Kp and Kc
(0)

Using Hess's Law To Determine K
(0)

Calculating K For Overall Reaction
(0)

Le Chatelier's Principle
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ICE Charts
(0)

Reaction Quotient
(0)

17. Acid and Base Equilibrium(0)

Acids Introduction
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Bases Introduction
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Binary Acids
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Oxyacids
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Bases
(0)

Amphoteric Species
(0)

Arrhenius Acids and Bases
(0)

Bronsted-Lowry Acids and Bases
(0)

Lewis Acids and Bases
(0)

The pH Scale
(0)

Auto-Ionization
(0)

Ka and Kb
(0)

pH of Strong Acids and Bases
(0)

Ionic Salts
(0)

pH of Weak Acids
(0)

pH of Weak Bases
(0)

Diprotic Acids and Bases
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Diprotic Acids and Bases Calculations
(0)

Triprotic Acids and Bases
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Triprotic Acids and Bases Calculations
(0)

18. Aqueous Equilibrium(0)

Intro to Buffers
(0)

Henderson-Hasselbalch Equation
(0)

Intro to Acid-Base Titration Curves
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Strong Titrate-Strong Titrant Curves
(0)

Weak Titrate-Strong Titrant Curves
(0)

Acid-Base Indicators
(0)

Titrations: Weak Acid-Strong Base
(0)

Titrations: Weak Base-Strong Acid
(0)

Titrations: Strong Acid-Strong Base
(0)

Titrations: Diprotic & Polyprotic Buffers
(0)

Solubility Product Constant: Ksp
(0)

Ksp: Common Ion Effect
(0)

Precipitation: Ksp vs Q
(0)

Selective Precipitation
(0)

Complex Ions: Formation Constant
(0)

19. Chemical Thermodynamics(0)

Spontaneous vs Nonspontaneous Reactions
(0)

Entropy
(0)

Entropy Calculations
(0)

Entropy Calculations: Phase Changes
(0)

Third Law of Thermodynamics
(0)

Gibbs Free Energy
(0)

Gibbs Free Energy Calculations
(0)

Gibbs Free Energy And Equilibrium
(0)

20. Electrochemistry(0)

Standard Reduction Potentials
(0)

Intro to Electrochemical Cells
(0)

Galvanic Cell
(0)

Electrolytic Cell
(0)

Cell Potential: Standard
(0)

Cell Potential: The Nernst Equation
(0)

Cell Potential and Gibbs Free Energy
(0)

Cell Potential and Equilibrium
(0)

Cell Potential: G and K
(0)

Cell Notation
(0)

Electroplating
(0)

21. Nuclear Chemistry(0)

Intro to Radioactivity
(0)

Alpha Decay
(0)

Beta Decay
(0)

Gamma Emission
(0)

Electron Capture & Positron Emission
(0)

Neutron to Proton Ratio
(0)

Band of Stability: Alpha Decay & Nuclear Fission
(0)

Band of Stability: Beta Decay
(0)

Band of Stability: Electron Capture & Positron Emission
(0)

Band of Stability: Overview
(0)

Measuring Radioactivity
(0)

Rate of Radioactive Decay
(0)

Radioactive Half-Life
(0)

Mass Defect
(0)

Nuclear Binding Energy
(0)

22. Organic Chemistry(0)

Introduction to Organic Chemistry
(0)

Structural Formula
(0)

Condensed Formula
(0)

Skeletal Formula
(0)

Spatial Orientation of Bonds
(0)

Intro to Hydrocarbons
(0)

Isomers
(0)

Chirality
(0)

Functional Groups in Chemistry
(0)

Naming Alkanes
(0)

The Alkyl Groups
(0)

Naming Alkanes with Substituents
(0)

Naming Cyclic Alkanes
(0)

Naming Other Substituents
(0)

Naming Alcohols
(0)

Naming Alkenes
(0)

Naming Alkynes
(0)

Naming Ketones
(0)

Naming Aldehydes
(0)

Naming Carboxylic Acids
(0)

Naming Esters
(0)

Naming Ethers
(0)

Naming Amines
(0)

Naming Benzene
(0)

Alkane Reactions
(0)

Intro to Addition Reactions
(0)

Halogenation Reactions
(0)

Hydrogenation Reactions
(0)

Hydrohalogenation Reactions
(0)

Alcohol Reactions: Substitution Reactions
(0)

Alcohol Reactions: Dehydration Reactions
(0)

Intro to Redox Reactions
(0)

Alcohol Reactions: Oxidation Reactions
(0)

Aldehydes and Ketones Reactions
(0)

Ester Reactions: Esterification
(0)

Ester Reactions: Saponification
(0)

Carboxylic Acid Reactions
(0)

Amine Reactions
(0)

Amide Formation
(0)

Benzene Reactions
(0)

23. Chemistry of the Nonmetals(0)

Main Group Elements: Bonding Types
(0)

Main Group Elements: Boiling & Melting Points
(0)

Main Group Elements: Density
(0)

Main Group Elements: Periodic Trends
(0)

The Electron Configuration Review
(0)

Periodic Table Charges Review
(0)

Hydrogen Isotopes
(0)

Hydrogen Compounds
(0)

Production of Hydrogen
(0)

Group 1A and 2A Reactions
(0)

Boron Family Reactions
(0)

Boron Family: Borane
(0)

Borane Reactions
(0)

Nitrogen Family Reactions
(0)

Oxides, Peroxides, and Superoxides
(0)

Oxide Reactions
(0)

Peroxide and Superoxide Reactions
(0)

Noble Gas Compounds
(0)

24. Transition Metals and Coordination Compounds(0)

Atomic Radius & Density of Transition Metals
(0)

Electron Configurations of Transition Metals
(0)

Electron Configurations of Transition Metals: Exceptions
(0)

Paramagnetism and Diamagnetism
(0)

Ligands
(0)

Complex Ions
(0)

Coordination Complexes
(0)

Classification of Ligands
(0)

Coordination Numbers & Geometry
(0)

Naming Coordination Compounds
(0)

Writing Formulas of Coordination Compounds
(0)

Isomerism in Coordination Complexes
(0)

Orientations of D Orbitals
(0)

Intro to Crystal Field Theory
(0)

Crystal Field Theory: Octahedral Complexes
(0)

Crystal Field Theory: Tetrahedral Complexes
(0)

Crystal Field Theory: Square Planar Complexes
(0)

Crystal Field Theory Summary
(0)

Magnetic Properties of Complex Ions
(0)

Strong-Field vs Weak-Field Ligands
(0)

Magnetic Properties of Complex Ions: Octahedral Complexes
(0)

7. Gases

Mole Fraction of Gases

7. Gases

Mole Fraction of Gases: Videos & Practice Problems

Video Lessons Practice Worksheet

Mole Fraction of Gases Practice Problems

20 problems

Problem 1Multiple Choice

Carbon dioxide, CO₂, is previously used as a refrigerant. Raw CO₂ gas is a by-product during the fermentation of sugars. To lessen the amount of CO₂ that is released into the atmosphere, raw CO₂ gas undergoes treatment and can be liquefied. The treated CO₂ gas is stored in tank A and the liquefied CO₂ is stored in tank B. The solubility of O₂ gas in the liquefied CO₂ is 0.0150 mL O₂ per 100 mL liquefied CO₂ whereas the treated CO₂ gas contains 0.0200% O₂ gas by volume. Listed in the following table are the parameters of tank A and tank B. Calculate the moles of O₂ gas present in tank A and tank B.

Volume (L) Pressure (atm) Temperature (°C)

Tank A 250 1.00 atm 35.0°C

Tank B 250 75.0 atm 20.0°C

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Problem 2Multiple Choice

The following apparatus shows three enclosed 0.500 L bulbs connected by stopcocks. Bulb X at 200°C has a total pressure of 650 mmHg and contains Br₂(g), I₂(g), and Cl₂(g). Bulb Y and Bulb Z are both empty and held at a temperature of 95.0°C and 25.0°C, respectively. Initially, the stopcocks are closed. Assume that the volume of the lines joining the bulbs is negligible.

Diagram of three bulbs X, Y, Z showing gas pressures and temperatures for chemistry experiment.

When the stopcock between X and Y opened and the mixture was allowed to reach equilibrium, X and Y had a total pressure of 270 mmHg. What is contained in bulbs X and Y?

Useful information:

Table listing boiling and melting points of Cl2, Br2, and I2 for chemistry reference.

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Problem 3Multiple Choice

What is the average molecular weight of moist air? Use the information below:

Table showing the volume percentages of gases in moist air for chemistry course.

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Problem 4Multiple Choice

Calculate the mole fraction of Ar in the atmosphere, if its atmospheric concentration is 9,340 ppm (parts per million, by volume; that is, 9,340 L of every 10⁶ L of the atmosphere are Ar)

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Problem 5Multiple Choice

Exhaled air has an average oxygen composition of 16% by volume. Calculate the partial pressure of the oxygen assuming a temperature of 25°C and 1 atm pressure.

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Problem 6Multiple Choice

A flask contains 16.3 g Xe, 7.52 g Cl₂, and 4.15 g He. Calculate the mole fraction of Cl₂ in the flask.

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Problem 7Multiple Choice

A vessel contains CO, H₂, and O₂. The mole fractions of H₂ and O₂ are 0.17 and 0.62, respectively. What would be the mole fraction of CO?

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Problem 8Multiple Choice

Calculate the mole fraction of oxygen in the air. If air contains 18.0 g oxygen gas at 285 K at 1.20 atm, what is the volume of air?

Table showing the composition of dry air by volume, highlighting nitrogen, oxygen, argon, and carbon dioxide.

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Problem 9Multiple Choice

Determine the mole fraction of each component given the following data:

Component Mass (g)

N₂ 0.700

O₂0.800

Cl₂1.77

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Problem 10Multiple Choice

What does the variable x represent in the context of mole fraction?

Problem 11Multiple Choice

Which of the following best describes a mole component in relation to mole fraction?

Problem 12Multiple Choice

A mixture contains 3 moles of nitrogen and 1 mole of oxygen. Calculate the mole fraction of oxygen.

Problem 13Multiple Choice

In a laboratory experiment, you have a gas mixture containing helium, neon, and argon. If you need to calculate the mole fraction of neon, which information is necessary?

Problem 14Multiple Choice

Given a mixture of gases with 2 moles of hydrogen, 3 moles of oxygen, and 5 moles of nitrogen, demonstrate the calculation of the mole fraction of oxygen.

Problem 15Multiple Choice

Why is understanding mole fraction important in the study of gas mixtures?

Problem 16Multiple Choice

A gas mixture consists of 4 moles of carbon dioxide, 2 moles of methane, and 3 moles of nitrogen. How would you determine the mole fraction of methane?

Problem 17Multiple Choice

In a scuba diving tank, the mixture contains 21% oxygen and 79% nitrogen by mole fraction. Explain how understanding mole fraction is crucial for safe diving practices.

Problem 18Multiple Choice

Which formula represents the mole fraction of a component in a mixture?

Problem 19Multiple Choice

Why is the mole component significant when calculating mole fraction?

Problem 20Multiple Choice

If a solution contains 2 moles of solute C and 8 moles of solvent D, what is the mole fraction of solute C?