객관식
What are the fossils called that help scientists to identify or date rocks or fossils?
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목차
- 1. A Review of General Chemistry5h 6m
- Summary23m
- Intro to Organic Chemistry4m
- Atomic Structure17m
- Wave Function9m
- Molecular Orbitals17m
- Sigma and Pi Bonds10m
- Octet Rule12m
- Bonding Preferences12m
- Formal Charges6m
- Skeletal Structure14m
- Lewis Structure20m
- Condensed Structural Formula15m
- Degrees of Unsaturation15m
- Constitutional Isomers14m
- Resonance Structures46m
- Hybridization23m
- Molecular Geometry16m
- Electronegativity22m
- 2. Molecular Representations1h 14m
- 3. Acids and Bases2h 46m
- 4. Alkanes and Cycloalkanes4h 34m
- IUPAC Naming29m
- Alkyl Groups13m
- Naming Cycloalkanes10m
- Naming Bicyclic Compounds10m
- Naming Alkyl Halides7m
- Naming Alkenes3m
- Naming Alcohols8m
- Naming Amines13m
- Cis vs Trans21m
- Conformational Isomers13m
- Newman Projections14m
- Drawing Newman Projections16m
- Barrier To Rotation9m
- Ring Strain9m
- Axial vs Equatorial7m
- Cis vs Trans Conformations4m
- Equatorial Preference14m
- Chair Flip9m
- Calculating Energy Difference Between Chair Conformations26m
- A-Values17m
- Decalin12m
- 5. Chirality3h 39m
- Constitutional Isomers vs. Stereoisomers9m
- Chirality12m
- Test 1:Plane of Symmetry7m
- Test 2:Stereocenter Test17m
- R and S Configuration43m
- Enantiomers vs. Diastereomers13m
- Atropisomers9m
- Meso Compound12m
- Test 3:Disubstituted Cycloalkanes13m
- What is the Relationship Between Isomers?16m
- Fischer Projection10m
- R and S of Fischer Projections7m
- Optical Activity5m
- Enantiomeric Excess20m
- Calculations with Enantiomeric Percentages11m
- Non-Carbon Chiral Centers8m
- 6. Thermodynamics and Kinetics1h 22m
- 7. Substitution Reactions1h 48m
- 8. Elimination Reactions2h 30m
- 9. Alkenes and Alkynes2h 9m
- 10. Addition Reactions3h 19m
- Addition Reaction6m
- Markovnikov5m
- Hydrohalogenation6m
- Acid-Catalyzed Hydration16m
- Oxymercuration15m
- Hydroboration26m
- Hydrogenation6m
- Halogenation6m
- Halohydrin12m
- Carbene12m
- Epoxidation8m
- Epoxide Reactions9m
- Dihydroxylation8m
- Ozonolysis7m
- Ozonolysis Full Mechanism24m
- Oxidative Cleavage3m
- Alkyne Oxidative Cleavage6m
- Alkyne Hydrohalogenation3m
- Alkyne Halogenation2m
- Alkyne Hydration7m
- Alkyne Hydroboration2m
- 11. Radical Reactions1h 58m
- 12. Alcohols, Ethers, Epoxides and Thiols2h 40m
- Alcohol Nomenclature4m
- Naming Ethers6m
- Naming Epoxides18m
- Naming Thiols11m
- Alcohol Synthesis7m
- Leaving Group Conversions - Using HX11m
- Leaving Group Conversions - SOCl2 and PBr313m
- Leaving Group Conversions - Sulfonyl Chlorides5m
- Leaving Group Conversions Summary4m
- Williamson Ether Synthesis3m
- Making Ethers - Alkoxymercuration4m
- Making Ethers - Alcohol Condensation4m
- Making Ethers - Acid-Catalyzed Alkoxylation4m
- Making Ethers - Cumulative Practice10m
- Ether Cleavage8m
- Alcohol Protecting Groups3m
- t-Butyl Ether Protecting Groups5m
- Silyl Ether Protecting Groups10m
- Sharpless Epoxidation9m
- Thiol Reactions6m
- Sulfide Oxidation4m
- 13. Alcohols and Carbonyl Compounds2h 17m
- 14. Synthetic Techniques1h 26m
- 15. Analytical Techniques:IR, NMR, Mass Spect7h 3m
- Purpose of Analytical Techniques5m
- Infrared Spectroscopy16m
- Infrared Spectroscopy Table31m
- IR Spect:Drawing Spectra40m
- IR Spect:Extra Practice26m
- NMR Spectroscopy10m
- 1H NMR:Number of Signals26m
- 1H NMR:Q-Test26m
- 1H NMR:E/Z Diastereoisomerism8m
- H NMR Table24m
- 1H NMR:Spin-Splitting (N + 1) Rule22m
- 1H NMR:Spin-Splitting Simple Tree Diagrams11m
- 1H NMR:Spin-Splitting Complex Tree Diagrams12m
- 1H NMR:Spin-Splitting Patterns8m
- NMR Integration18m
- NMR Practice14m
- Carbon NMR4m
- Structure Determination without Mass Spect47m
- Mass Spectrometry12m
- Mass Spect:Fragmentation28m
- Mass Spect:Isotopes27m
- 16. Conjugated Systems6h 13m
- Conjugation Chemistry13m
- Stability of Conjugated Intermediates4m
- Allylic Halogenation12m
- Reactions at the Allylic Position39m
- Conjugated Hydrohalogenation (1,2 vs 1,4 addition)26m
- Diels-Alder Reaction9m
- Diels-Alder Forming Bridged Products11m
- Diels-Alder Retrosynthesis8m
- Molecular Orbital Theory9m
- Drawing Atomic Orbitals6m
- Drawing Molecular Orbitals17m
- HOMO LUMO4m
- Orbital Diagram:3-atoms- Allylic Ions13m
- Orbital Diagram:4-atoms- 1,3-butadiene11m
- Orbital Diagram:5-atoms- Allylic Ions10m
- Orbital Diagram:6-atoms- 1,3,5-hexatriene13m
- Orbital Diagram:Excited States4m
- Pericyclic Reaction10m
- Thermal Cycloaddition Reactions26m
- Photochemical Cycloaddition Reactions26m
- Thermal Electrocyclic Reactions14m
- Photochemical Electrocyclic Reactions10m
- Cumulative Electrocyclic Problems25m
- Sigmatropic Rearrangement17m
- Cope Rearrangement9m
- Claisen Rearrangement15m
- 17. Ultraviolet Spectroscopy51m
- 18. Aromaticity2h 34m
- 19. Reactions of Aromatics: EAS and Beyond5h 2m
- Electrophilic Aromatic Substitution9m
- Benzene Reactions11m
- EAS:Halogenation Mechanism6m
- EAS:Nitration Mechanism9m
- EAS:Friedel-Crafts Alkylation Mechanism6m
- EAS:Friedel-Crafts Acylation Mechanism5m
- EAS:Any Carbocation Mechanism7m
- Electron Withdrawing Groups22m
- EAS:Ortho vs. Para Positions4m
- Acylation of Aniline9m
- Limitations of Friedel-Crafts Alkyation19m
- Advantages of Friedel-Crafts Acylation6m
- Blocking Groups - Sulfonic Acid12m
- EAS:Synergistic and Competitive Groups13m
- Side-Chain Halogenation6m
- Side-Chain Oxidation4m
- Reactions at Benzylic Positions32m
- Birch Reduction10m
- EAS:Sequence Groups4m
- EAS:Retrosynthesis29m
- Diazo Replacement Reactions6m
- Diazo Sequence Groups5m
- Diazo Retrosynthesis13m
- Nucleophilic Aromatic Substitution28m
- Benzyne16m
- 20. Phenols55m
- 21. Aldehydes and Ketones: Nucleophilic Addition4h 56m
- Naming Aldehydes8m
- Naming Ketones7m
- Oxidizing and Reducing Agents9m
- Oxidation of Alcohols28m
- Ozonolysis7m
- DIBAL5m
- Alkyne Hydration9m
- Nucleophilic Addition8m
- Cyanohydrin11m
- Organometallics on Ketones19m
- Overview of Nucleophilic Addition of Solvents13m
- Hydrates6m
- Hemiacetal9m
- Acetal12m
- Acetal Protecting Group16m
- Thioacetal6m
- Imine vs Enamine15m
- Addition of Amine Derivatives5m
- Wolff Kishner Reduction7m
- Baeyer-Villiger Oxidation39m
- Acid Chloride to Ketone7m
- Nitrile to Ketone9m
- Wittig Reaction18m
- Ketone and Aldehyde Synthesis Reactions14m
- 22. Carboxylic Acid Derivatives: NAS2h 51m
- Carboxylic Acid Derivatives7m
- Naming Carboxylic Acids9m
- Diacid Nomenclature6m
- Naming Esters5m
- Naming Nitriles3m
- Acid Chloride Nomenclature5m
- Naming Anhydrides7m
- Naming Amides5m
- Nucleophilic Acyl Substitution18m
- Carboxylic Acid to Acid Chloride6m
- Fischer Esterification5m
- Acid-Catalyzed Ester Hydrolysis4m
- Saponification3m
- Transesterification5m
- Lactones, Lactams and Cyclization Reactions10m
- Carboxylation5m
- Decarboxylation Mechanism14m
- Review of Nitriles46m
- 23. The Chemistry of Thioesters, Phophate Ester and Phosphate Anhydrides1h 10m
- 24. Enolate Chemistry: Reactions at the Alpha-Carbon1h 50m
- Tautomerization9m
- Tautomers of Dicarbonyl Compounds6m
- Enolate4m
- Acid-Catalyzed Alpha-Halogentation4m
- Base-Catalyzed Alpha-Halogentation3m
- Haloform Reaction8m
- Hell-Volhard-Zelinski Reaction3m
- Overview of Alpha-Alkylations and Acylations6m
- Enolate Alkylation and Acylation12m
- Enamine Alkylation and Acylation16m
- Beta-Dicarbonyl Synthesis Pathway7m
- Acetoacetic Ester Synthesis13m
- Malonic Ester Synthesis12m
- 25. Condensation Chemistry2h 9m
- 26. Amines1h 43m
- 27. Heterocycles2h 0m
- Nomenclature of Heterocycles15m
- Acid-Base Properties of Nitrogen Heterocycles10m
- Reactions of Pyrrole, Furan, and Thiophene13m
- Directing Effects in Substituted Pyrroles, Furans, and Thiophenes16m
- Addition Reactions of Furan8m
- EAS Reactions of Pyridine17m
- SNAr Reactions of Pyridine18m
- Side-Chain Reactions of Substituted Pyridines20m
- 28. Carbohydrates5h 54m
- Monosaccharide20m
- Monosaccharides - D and L Isomerism9m
- Monosaccharides - Drawing Fischer Projections18m
- Monosaccharides - Common Structures6m
- Monosaccharides - Forming Cyclic Hemiacetals12m
- Monosaccharides - Cyclization18m
- Monosaccharides - Haworth Projections13m
- Mutarotation11m
- Epimerization9m
- Monosaccharides - Aldose-Ketose Rearrangement8m
- Monosaccharides - Alkylation10m
- Monosaccharides - Acylation8m
- Glycoside6m
- Monosaccharides - N-Glycosides18m
- Monosaccharides - Reduction (Alditols)12m
- Monosaccharides - Weak Oxidation (Aldonic Acid)7m
- Reducing Sugars23m
- Monosaccharides - Strong Oxidation (Aldaric Acid)11m
- Monosaccharides - Oxidative Cleavage27m
- Monosaccharides - Osazones10m
- Monosaccharides - Kiliani-Fischer23m
- Monosaccharides - Wohl Degradation12m
- Monosaccharides - Ruff Degradation12m
- Disaccharide30m
- Polysaccharide11m
- 29. Amino Acids4h 16m
- Proteins and Amino Acids19m
- L and D Amino Acids14m
- Polar Amino Acids14m
- Amino Acid Chart1h 14m
- Acid-Base Properties of Amino Acids33m
- Isoelectric Point14m
- Amino Acid Synthesis: HVZ Method12m
- Synthesis of Amino Acids: Acetamidomalonic Ester Synthesis16m
- Synthesis of Amino Acids: N-Phthalimidomalonic Ester Synthesis13m
- Synthesis of Amino Acids: Strecker Synthesis13m
- Reactions of Amino Acids: Esterification7m
- Reactions of Amino Acids: Acylation3m
- Reactions of Amino Acids: Hydrogenolysis6m
- Reactions of Amino Acids: Ninhydrin Test11m
- 30. Peptides and Proteins2h 42m
- Peptides12m
- Primary Protein Structure4m
- Secondary Protein Structure17m
- Tertiary Protein Structure11m
- Disulfide Bonds17m
- Quaternary Protein Structure10m
- Summary of Protein Structure7m
- Intro to Peptide Sequencing2m
- Peptide Sequencing: Partial Hydrolysis25m
- Peptide Sequencing: Partial Hydrolysis with Cyanogen Bromide7m
- Peptide Sequencing: Edman Degradation28m
- Merrifield Solid-Phase Peptide Synthesis18m
- 31. Catalysis in Organic Reactions1h 30m
- 32. Lipids 2h 50m
- 33. The Organic Chemistry of Metabolic Pathways2h 52m
- Intro to Metabolism6m
- ATP and Energy6m
- Intro to Coenzymes3m
- Coenzymes in Metabolism16m
- Energy Production in Biochemical Pathways5m
- Intro to Glycolysis3m
- Catabolism of Carbohydrates: Glycolysis27m
- Glycolysis Summary15m
- Pyruvate Oxidation (Simplified)4m
- Anaerobic Respiration11m
- Catabolism of Fats: Glycerol Metabolism11m
- Intro to Citric Acid Cycle7m
- Structures of the Citric Acid Cycle19m
- The Citric Acid Cycle35m
- 34. Nucleic Acids1h 32m
- 35. Transition Metals6h 14m
- Electron Configuration of Elements45m
- Coordination Complexes20m
- Ligands24m
- Electron Counting10m
- The 18 and 16 Electron Rule13m
- Cross-Coupling General Reactions40m
- Heck Reaction40m
- Stille Reaction13m
- Suzuki Reaction25m
- Sonogashira Coupling Reaction17m
- Fukuyama Coupling Reaction15m
- Kumada Coupling Reaction13m
- Negishi Coupling Reaction16m
- Buchwald-Hartwig Amination Reaction19m
- Eglinton Reaction17m
- Catalytic Allylic Alkylation18m
- Alkene Metathesis23m
- 36. Synthetic Polymers1h 49m
- Introduction to Polymers6m
- Chain-Growth Polymers10m
- Radical Polymerization15m
- Cationic Polymerization8m
- Anionic Polymerization8m
- Polymer Stereochemistry3m
- Ziegler-Natta Polymerization4m
- Copolymers6m
- Step-Growth Polymers11m
- Step-Growth Polymers: Urethane6m
- Step-Growth Polymers: Polyurethane Mechanism10m
- Step-Growth Polymers: Epoxy Resin8m
- Polymers Structure and Properties8m
1. A Review of General Chemistry
Intro to Organic Chemistry
객관식
In the context of organic chemistry, when are the first organic molecules thought to have existed?
A
Approximately
B
Approximately
C
Approximately
D
Approximately
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검증된 단계별 안내1
Understand the context of the question: It is asking about the timeline of the existence of the first organic molecules on Earth.
Consider the history of Earth: Earth is approximately 4.5 billion years old, and life is thought to have begun relatively early in its history.
Recognize the significance of organic molecules: Organic molecules are essential for life, and their formation is a key step in the development of life on Earth.
Research scientific evidence: Studies of ancient rocks and fossils suggest that life, and thus organic molecules, existed around 3.5 billion years ago.
Evaluate the options given: Compare the timeline of Earth's history and the emergence of life to the options provided to determine the most scientifically supported answer.
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