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Understanding Redox Reactions and Half-Reactions Study Guide

This guide provides a comprehensive overview of redox reactions, focusing on the core principles of oxidation and reduction. It details the concept of half-reactions as a method to analyze electron transfer processes. The guide includes a step-by-step approach to balancing complex redox reactions, essential for understanding chemical transformations in various contexts such as batteries, corrosion, and biological energy transfer. Key takeaways include the OIL RIG mnemonic and a summary table of

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Energy Quantization and Atomic Transitions

Black Body Radiation and Energy Quantization

  • black body radiation
  • ultraviolet catastrophe
  • energy quantization
  • electromagnetic spectrum
  • photoelectric effect

Energy Quantization and Light Phenomena

An exploration of energy quantization through the photoelectric effect, photon behavior, and discrete line spectra.

  • Photoelectric effect
  • Photons
  • Energy quantization
  • Work function
  • Kinetic energy
  • Planck constant
  • Line spectra
  • Bohr model
  • Energy states

Metal Atom Excitation and Emission Spectra

Exciting metal atoms with a propane torch flame causes electrons to transition and emit specific colors of light.

  • Metal atoms
  • Electron excitation
  • Electron relaxation
  • Emission spectra
  • Line spectra
  • Wavelength
  • Flame test

Energy Transitions in the Hydrogen Atom

Electrons in a hydrogen atom transition between quantized energy states by absorbing or emitting photons.

  • Energy transitions
  • Hydrogen atom
  • Quantized energy states
  • Photon absorption
  • Photon emission
  • Line spectrum

Quantum Numbers, Atomic Orbitals, and Nodal Structures

Quantum Numbers and Atomic Orbitals

An exploration of the four quantum numbers that specify unique atomic orbitals and the Pauli exclusion principle.

  • Principal quantum number (n)
  • Angular momentum quantum number (l)
  • Magnetic quantum number (ml)
  • Spin magnetic quantum number (ms)
  • Atomic orbitals
  • Subshells
  • Electron spin

Orbital Shapes and Nodal Properties

This content explains S and P orbital shapes, probability densities, radial probability distributions, and the mathematical rules governing radial and angular nodes.

  • S orbitals
  • P orbitals
  • Probability density
  • Radial probability distribution
  • Wave function (psi)
  • Angular node
  • Radial node
  • Principal quantum number (n)
  • Angular momentum quantum number (l)
  • Magnetic quantum number (ml)
  • Degenerate orbitals

Probability Density and Atomic Orbitals

This content discusses the probability density of finding an electron in P and D orbitals, wave function oscillations, and angular nodes.

  • Probability density
  • Atomic orbitals
  • P orbitals
  • D orbitals
  • Wave function
  • Angular nodes
  • Electron distribution

Wave Function Nodes and D Orbitals

Electrons are described by a wave function acting as a three-dimensional standing wave where nodes occur when the wave function changes sign.

  • Wave function
  • Standing wave
  • Nodes
  • D orbitals
  • Angular nodes
  • Radial nodes
  • Electron density

Atomic Orbital Nodes and Quantum Numbers

An analysis of atomic orbitals, nodal structures, and the relationships between quantum numbers.

  • Atomic orbitals
  • Nodal structures
  • Quantum numbers
  • Radial nodes
  • Angular nodes
  • S orbitals
  • D orbitals

Nodes and Structure of D Orbitals

An analysis of angular and radial nodes within s, p, and d orbitals and their relationship to the principal quantum number.

  • Nodes
  • D orbitals
  • Angular nodes
  • Radial nodes
  • Principal quantum number
  • S orbitals
  • P orbitals

Quantum Numbers and Electron Configurations

An exploration of the Pauli exclusion principle, excited states, and orbital filling rules in electron configurations.

  • Quantum numbers
  • Electron configurations
  • Excited states
  • Orbital filling rules
  • Ground state

Drawing and Evaluating Lewis Structures

Drawing Lewis Dot Structures and Formal Charge

This content explains how to determine total valence electrons, draw Lewis dot structures, and evaluate formal charges for neutral molecules and molecular ions.

  • molecular ions
  • electronegativity
  • bonding electrons
  • lone pair electrons
  • formal charge
  • covalent electrons
  • octet rule
  • hypervalent species
  • expanded octet

Chemical Equation Fundamentals

Reactants and Products

Understanding the distinction between substances undergoing reaction (reactants) and substances generated (products).

Chemical Formulas and Symbols

How element symbols and subscripts are used to represent individual atoms, ions, and molecules in a reaction.

  • Chemical formulas
  • Element symbols
  • Subscripts
  • Atoms
  • Molecules

Coefficients and Ratios

Using whole-number coefficients to represent the relative quantities and molar ratios of reactants and products.

  • Coefficients
  • Molar ratios
  • Reactants
  • Products
  • Balanced equation

Equation Notation and Symbols

Mastering the use of plus signs, arrows, and special symbols like delta for heating.

  • Chemical equation notation
  • Plus signs
  • Arrows
  • Delta symbol
  • Heating

Precipitation Reactions

Introduction to Precipitation

Understanding how dissolved substances react to form solid products, also known as metathesis or double displacement reactions.

Solubility and Concentration

Defining solubility as the maximum concentration of a substance in a solvent and understanding when precipitation occurs.

  • Solubility
  • Concentration
  • Solute
  • Precipitation
  • Solubility rules

Solubility Rules Mastery

Memorizing patterns for soluble and insoluble ions, including common exceptions for halides, sulfates, and hydroxides.

  • Solubility rules
  • Soluble ions
  • Precipitation
  • Exceptions

Predicting Precipitates

Learning to identify all possible cation/anion pairings in a mixture to predict if a solid will form.

  • Predicting precipitates
  • Cations
  • Solubility rules
  • Mixture

Reaction Stoichiometry Principles

Introduction to Stoichiometry

Defining stoichiometry and understanding how chemical formulas and coefficients provide quantitative information about reactions.

  • Stoichiometry
  • Balanced chemical equation
  • Molar ratios
  • Coefficients
  • Reactants
  • Products

Stoichiometric Factors

Learning how to derive ratios (factors) from balanced equations to relate different chemical species.

  • Stoichiometric factor
  • Molar ratio
  • Balanced equation
  • Mole-to-mole conversion

Mole-to-Mole Conversions

Using stoichiometric factors to calculate the molar amounts of reactants required or products produced.

  • Mole-to-mole conversion
  • Stoichiometric factor
  • Balanced equation
  • Moles
  • Reactants
  • Products

Particle Number Calculations

Using Avogadro's number to convert between moles and the absolute number of molecules or atoms.

  • Particle number
  • Moles
  • Molecules
  • Atoms
  • Conversion

Limiting and Excess Reactants

Stoichiometric vs. Non-Stoichiometric Amounts

Distinguishing between reactions where reactants are in perfect ratios versus real-world scenarios where one reactant is in excess.

  • Stoichiometric amounts
  • Non-stoichiometric amounts
  • Limiting reactant
  • Excess reactant
  • Theoretical yield

Identifying Limiting Reactants via Molar Ratios

Comparing the provided molar amounts of reactants to the balanced chemical equation to identify which will be consumed first.

  • Limiting reactant
  • Excess reactant
  • Molar ratios
  • Balanced equation
  • Stoichiometry

Identifying Limiting Reactants via Product Yield

An alternative method where you calculate the expected product from each reactant; the reactant yielding the least product is the limiting one.

  • Limiting reactant
  • Product yield
  • Stoichiometry
  • Calculation method
  • Theoretical yield

Calculating Excess Reactant Remaining

Determining how much of the non-limiting reactant remains unreacted after the limiting reactant is completely consumed.

  • Excess reactant
  • Limiting reactant
  • Unreacted amount
  • Stoichiometry
  • Calculation

Quantitative Chemical Analysis

Principles of Quantitative Analysis

Understanding the difference between qualitative and quantitative analysis and how concentration is determined through chemical reactions.

  • Quantitative analysis
  • Qualitative analysis
  • Concentration determination
  • Chemical reactions
  • Analytical chemistry

Analyte and Titrant Definitions

Distinguishing between the substance being measured (analyte) and the substance of known concentration (titrant).

  • Analyte
  • Titrant
  • Quantitative analysis
  • Titration
  • Known concentration

Stoichiometry in Analysis

Using balanced chemical equations to relate the amounts of reactants and products in analytical procedures.

  • Stoichiometry
  • Quantitative analysis
  • Balanced chemical equations
  • Analytical procedures
  • Reactants
  • Products

Quantum Mechanical Models and Atomic Orbitals

Quantum Numbers and Atomic Orbitals

An explanation of the quantum mechanical model, specifically focusing on the differences between Bohr orbits and orbitals, and the application of quantum numbers to describe electron probability and orbital shapes.

  • Orbital
  • Quantum mechanical model
  • Schrodinger equation
  • Wave function
  • Principal quantum number (N)
  • Angular momentum quantum number (L)
  • Magnetic quantum number (ML)
  • S, P, and D orbitals
  • Electron shell
  • Probability density

Quantum Mechanical Orbitals and Nodes

An exploration of wave functions, probability density, and radial nodes within S orbitals.

  • wave function
  • probability density
  • Schrodinger equation
  • orbital
  • nodes
  • radial nodes
  • principal quantum number
  • relative phase

Accessing Echo 360 Polling Questions

Instructions for accessing Echo 360 polling questions through Bright Space and managing technical issues.

  • Polling questions
  • Bright Space
  • Technical issues
  • Browser cache
  • Cookies

Electronic Structure and Periodic Properties

An overview of the transition from the Bohr model of the atom to the modern understanding of atomic orbitals and wave-particle duality.

  • Bohr model
  • Atomic orbitals
  • Wave-particle duality
  • Schrodinger equation
  • Electromagnetic radiation

Electron Configurations, Atomic Orbitals, and Periodic Trends

Relative Energies of Atomic Orbitals

Orbital energies increase with increasing N and L due to spatial extension and electrostatic attraction to the nucleus.

  • Atomic orbital capacity
  • Degenerate orbitals
  • Orbital energy trends
  • Principal quantum number (N)
  • Angular momentum quantum number (L)
  • Electrostatic attraction
  • Angular nodes
  • Effective nuclear charge

Condensed Electron Configurations and Periodic Blocks

This lecture covers condensed electron configurations, orbital filling orders, and the organization of the periodic table into s, p, d, and f blocks.

  • condensed electron configurations
  • core electrons
  • s block
  • d block
  • f block
  • principal quantum number
  • orbital filling order
  • degenerate orbitals

Electron Configurations and Condensed Notation

  • Electron configuration
  • Condensed notation
  • Core electrons
  • Orbital filling order
  • Hund's rule
  • Aufbau principle

Quantum States and Electron Configurations

This discussion covers electron configurations, the Pauli exclusion principle, Hund's rule, and the distinctions between ground and excited states.

  • Quantum states
  • Electron configuration
  • Hund's rule
  • Ground state
  • Excited state
  • Orbital filling

Atomic Orbitals and Periodic Trends

  • Atomic orbitals
  • Periodic trends
  • Orbital energy levels
  • Principal quantum number
  • Atomic radius
  • Covalent radius
  • Metallic radius

Effective Nuclear Charge and Atomic Radius

The relationship between effective nuclear charge, core electron screening, and periodic trends in atomic radius.

  • Effective nuclear charge (Zeff)
  • Core electrons
  • Screening constant (S)
  • Atomic radius
  • Periodic trends
  • Shielding effect

Trends in Atomic Ionization Energy

An analysis of the energy required to remove successive electrons from gaseous atoms and how effective nuclear charge influences these trends.

  • Atomic ionization energy
  • Successive ionization
  • Gaseous atoms
  • Effective nuclear charge
  • Periodic trends
  • Electron removal

Completing Unit One and Midterm Preparation

Unit One Conclusion and Energy Concepts

The session finishes unit one covering chapter six and discusses ionization energy and electron affinity.

  • ionization energy
  • electron affinity

Lewis Structures, Formal Charges, and Resonance

Drawing Lewis Dot Structures and Resonance

Representations of Lewis dot structures involve formal charge, electronegative atoms, and resonance using double headed arrows.

  • Formal charge
  • Electronegative atoms
  • Resonance
  • Reconciled structures

Balancing Chemical Equations

Law of Conservation of Matter

The fundamental principle that atoms are neither created nor destroyed in a chemical reaction.

Balancing by Inspection

A qualitative approach to adjusting coefficients to balance elements on both sides of an equation.

  • Balancing equations
  • Coefficients
  • Conservation of mass
  • Inspection method

Subscripts vs. Coefficients

Crucial distinction between changing subscripts (which changes the substance) and changing coefficients (which changes the amount).

  • Subscripts
  • Coefficients
  • Chemical formulas
  • Balancing equations

Fractional Coefficients and Integer Conversion

Using intermediate fractional coefficients to balance complex equations and then converting to the smallest whole numbers.

  • Fractional coefficients
  • Integer conversion
  • Balancing equations
  • Complex equations

Physical State Notations

Identifying and using abbreviations for solids (s), liquids (l), gases (g), and aqueous solutions (aq).

  • Physical state notations
  • Solid (s)
  • Liquid (l)
  • Gas (g)
  • Aqueous (aq)
  • Chemical equations

Acid-Base Chemistry

Strong vs Weak Acids

Distinguishing between acids that dissociate completely (strong) and those that only partially react (weak).

  • Strong acids
  • Weak acids
  • Dissociation
  • Ionization
  • Acid strength
  • Equilibrium

Strong vs Weak Bases

  • Strong bases
  • Weak bases
  • Hydroxides
  • Dissociation

Neutralization Reactions

Studying the specific reaction between an acid and a base that typically produces water and a salt.

  • Neutralization reactions
  • Acid-base reaction
  • Water
  • Salt
  • pH

Real-World Acid-Base Examples

Applying concepts to everyday life, such as antacids in the stomach and culinary uses of baking soda.

  • Real-world examples
  • Acid-base chemistry
  • Antacids
  • Stomach acid
  • Baking soda
  • Culinary uses

Mass and Concentration Stoichiometry

Mass-to-Mass Conversions

The multi-step process of converting mass of one substance to mass of another via molar mass and stoichiometry.

  • Mass-to-mass conversion
  • Molar mass
  • Stoichiometric factor
  • Balanced equation

Molarity and Volume Relationships

Using solution concentration (molarity) to determine the moles of a reactant in a liquid volume.

  • Molarity
  • Solution concentration
  • Volume
  • Moles
  • Molar mass

Density and Mass Conversions

Applying density to convert between the volume of a pure substance and its mass.

  • Density
  • Mass
  • Volume
  • Pure substance
  • Conversion factors

Stoichiometry Flowchart Mastery

Synthesizing all conversion factors (molar mass, density, molarity, Avogadro's number) into a unified calculation strategy.

  • Stoichiometry flowchart
  • Conversion factors
  • Molar mass
  • Density
  • Molarity

Reaction Yield Analysis

Theoretical Yield Derivation

Calculating the maximum amount of product possible based on the limiting reactant and stoichiometry.

  • Theoretical yield
  • Limiting reactant
  • Stoichiometry
  • Balanced equation
  • Maximum product

Actual Yield Concepts

Understanding why experimental yields are often lower than theoretical yields due to side reactions, incomplete reactions, or collection losses.

  • Actual yield
  • Theoretical yield
  • Percent yield
  • Side reactions
  • Incomplete reactions
  • Collection losses

Percent Yield Calculations

Using the formula (Actual Yield / Theoretical Yield) * 100% to express reaction efficiency.

  • Percent yield
  • Actual yield
  • Theoretical yield
  • Reaction efficiency
  • Calculation formula

Yield Units and Conversions

Ensuring consistency in units (mass, moles, or volume) when calculating percent yield.

  • Yield units
  • Conversions
  • Percent yield
  • Mass
  • Moles
  • Volume

Titration Analysis

Titration Instrumentation and Setup

Mastering the use of a buret for precise volume measurements and understanding its markings.

  • Titration
  • Buret
  • Volume measurement
  • Molarity
  • Equivalence point

Equivalence Point vs End Point

Understanding the theoretical point of complete reaction versus the experimental point where a change is observed.

  • Equivalence point
  • Titration
  • Indicator
  • Complete reaction

Chemical Indicators

How special dyes are used to signal the end point of a titration through color changes.

  • Chemical indicators
  • Titration
  • Color change
  • Dyes

Titration Stoichiometry Calculations

Performing multi-step calculations involving volume, molarity, and stoichiometric factors to find unknown concentrations.

  • Titration
  • Stoichiometry
  • Calculations
  • Volume
  • Molarity
  • Unknown concentration

Millimole Shortcut Method

Using the relationship between molarity and millimoles per milliliter to simplify complex titration math.

  • Molarity
  • Titration
  • Shortcut method
  • Calculation simplification

Wave Nature and Quantum Duality

Understanding One and Two Dimensional Standing Waves

Standing waves are fixed at both ends and oscillate up and down without propagating through space.

  • Standing waves
  • Traveling waves
  • Nodes
  • Relative phase
  • Wavelength
  • Energy
  • One-dimensional standing waves
  • Two-dimensional standing waves

Quantum Mechanical Wave Functions and Orbitals

The relationship between standing waves, the Schrodinger equation, and the probability density of electrons in atoms.

  • Chladni plate
  • Standing waves
  • Nodes
  • Antinodes
  • Schrodinger equation
  • Wave function (psi)
  • Probability density (psi squared)
  • Energy quantization
  • Orbitals
  • S orbitals
  • P orbitals
  • D orbitals
  • Relative phase

Wave Characteristics and Electromagnetic Radiation

An exploration of wavelength, frequency, and the wave nature of electromagnetic radiation including interference and diffraction.

  • Wavelength
  • Frequency
  • Speed of light
  • Electromagnetic spectrum
  • Interference
  • Diffraction
  • Wave nature

Electron Wave-Particle Duality and Diffraction

  • Electron waves
  • Wave-particle duality
  • De Broglie wavelength
  • Electron diffraction
  • Electron microscope
  • Momentum

Matter Waves and De Broglie Wavelength

An exploration of matter waves, the De Broglie wavelength formula, and the comparison between subatomic particles and macroscopic objects.

  • Matter waves
  • De Broglie wavelength
  • Wave-particle duality
  • Subatomic particles
  • Macroscopic objects
  • Momentum

Ionization Energies and Exothermic Metal Reactions

Ionization Energy and Exothermic Reactions

Demonstrations involving sodium, lithium, potassium, and magnesium illustrate ionization energy, electron transfer, and exothermic reactions.

  • ionization energy
  • exothermic reaction
  • endothermic process
  • electron transfer
  • magnesium oxide
  • lattice energy
  • carbon dioxide
  • sodium
  • lithium
  • potassium
  • magnesium

Quantum Numbers and Electron Configurations

Three-Dimensional Atomic Orbitals and Electron Configurations

Analysis of quantum numbers, orbital shapes, and electron configurations including isoelectronic species and nuclear charge effects.

  • quantum numbers
  • angular momentum quantum number
  • p orbitals
  • spherically symmetric orbital
  • angular nodes
  • electron configuration
  • noble gas stability
  • isoelectronic
  • nuclear charge
  • principal quantum number

Lewis Structures and Bond Dissociation Energy

Lewis Structures and Bond Dissociation Energy

Drawing Lewis dot structures and calculating reaction enthalpy using bond dissociation energies.

  • formal charges
  • bond dissociation energy
  • endothermic
  • exothermic
  • enthalpy of reaction
  • covalent bonds
  • atomization energy

Ionic Reaction Formats

Molecular Equations

Writing equations that show complete chemical formulas for all reactants and products.

Complete Ionic Equations

Representing all dissolved strong electrolytes as dissociated ions to show the true state of the solution.

  • Complete ionic equation
  • Strong electrolytes
  • Aqueous solutions

Spectator Ions

Identifying ions that appear unchanged on both sides of a reaction and do not participate in the chemical change.

  • Spectator ions
  • Ionic equations
  • Chemical reactions

Oxidation-Reduction (Redox)

Oxidizing and Reducing Agents

Identifying which species is oxidized (the reductant) and which is reduced (the oxidant) in a reaction.

  • oxidizing agent
  • reducing agent
  • reductant
  • oxidant
  • oxidation
  • reduction

Assigning Oxidation Numbers

Applying formal rules to determine the oxidation state of elements in molecules and polyatomic ions.

  • oxidation numbers
  • oxidation state
  • rules for assigning oxidation numbers
  • elements
  • molecules
  • polyatomic ions

Redox Reaction Classification

Recognizing different types of redox, including combustion, single-displacement, and disproportionation reactions.

  • redox reactions
  • combustion reactions
  • single-displacement reactions
  • disproportionation reactions

Half-Reaction Balancing (Acidic)

A step-by-step systematic approach to balancing complex redox equations in acidic media using H2O and H+ ions.

  • balancing redox reactions
  • half-reaction method
  • acidic solution
  • H2O
  • H+

Half-Reaction Balancing (Basic)

Extending the half-reaction method to balance equations in basic media by incorporating OH- ions and water.

  • balancing redox reactions
  • half-reaction method
  • basic solution
  • OH-
  • H2O

Stoichiometry Applications

Combustion Reaction Calculations

Calculating reactant consumption and product formation in combustion processes like propane or octane.

  • Combustion reactions
  • Stoichiometry
  • Reactant consumption
  • Product formation
  • Propane

Airbag Deployment Chemistry

Analyzing the rapid decomposition of sodium azide (NaN3) to produce nitrogen gas for safety systems.

  • Airbags
  • Sodium azide (NaN3)
  • Decomposition reaction
  • Nitrogen gas (N2)
  • Stoichiometry

Gas Volume Generation

Predicting the volume of gas produced from a specific mass of solid reactant.

  • Gas volume
  • Stoichiometry
  • Solid reactant
  • Ideal gas law
  • Molar volume

Practical Problem Solving

Reviewing diverse examples including metal-acid reactions and antacid production.

  • Practical problems
  • Stoichiometry
  • Metal-acid reactions
  • Antacids
  • Problem-solving

Green Chemistry and Atom Economy

Principles of Green Chemistry

An introduction to the philosophy of designing chemical processes that minimize hazardous substances and waste.

  • Green chemistry
  • Hazardous substances
  • Waste minimization
  • Sustainable chemistry
  • Atom economy

Atom Economy Definition

Calculating the percentage by mass of the final product relative to the total mass of all reactants used.

  • Atom economy
  • Percent yield
  • Reactants
  • Products
  • Mass percentage

Atom Economy vs. Percent Yield

Distinguishing between the theoretical efficiency of a reaction pathway (atom economy) and the experimental success of a specific run (percent yield).

  • Atom economy
  • Percent yield
  • Theoretical efficiency
  • Experimental success
  • Reaction pathway

Case Study: Ibuprofen Synthesis

Comparing the traditional six-step ibuprofen synthesis to the modern BHC process to see the impact of improved atom economy.

  • Case study
  • Ibuprofen synthesis
  • Atom economy
  • Green chemistry
  • Process improvement

Gravimetric Analysis

Fundamentals of Gravimetry

Learning how changes in physical state (like precipitation) allow for the isolation and weighing of an analyte.

  • Gravimetry
  • Precipitation
  • Weighing
  • Analyte
  • Isolation

Precipitation and Filtration

The process of forming an insoluble solid, isolating it via filtration, and drying it for weighing.

  • Precipitation
  • Filtration
  • Drying
  • Weighing
  • Gravimetric analysis
  • Insoluble solid

Mass Percent Calculations

Calculating the concentration of a component in a mixture based on the mass of the isolated product.

  • Mass percent
  • Concentration
  • Mixture
  • Isolated product
  • Gravimetric analysis

Gravimetric Stoichiometry Workflows

Mastering the conversion chain: Mass of Precipitate -> Moles of Precipitate -> Moles of Analyte -> Mass of Analyte.

  • Gravimetric analysis
  • Stoichiometry
  • Conversion chain
  • Mass of precipitate
  • Moles of analyte
  • Mass of analyte

Combustion Analysis

Combustion Principles

  • Combustion analysis
  • Organic samples
  • Oxygen
  • Gaseous products
  • Carbon dioxide (CO2)
  • Water (H2O)

Absorption and Collection

Understanding how specific chemical absorbers (like NaOH for CO2) are used to capture combustion products.

  • Combustion analysis
  • Absorption
  • Collection
  • Chemical absorbers
  • Sodium hydroxide (NaOH)
  • Carbon dioxide (CO2)

Determining Elemental Mass

  • Elemental mass
  • Carbon
  • Hydrogen
  • Combustion analysis
  • Carbon dioxide (CO2)
  • Water (H2O)

Empirical Formula Derivation

Using molar ratios of carbon and hydrogen to determine the simplest whole-number ratio for an organic compound.

  • Empirical formula
  • Combustion analysis
  • Molar ratios
  • Carbon
  • Hydrogen
  • Organic compounds

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