Organic chemistry: choose a route from electron movement to equilibrium
Choose one explanatory spine rather than memorizing three lists of reactions. The six outputs connect structures, electron movement, equilibrium and the limits of a prediction. The worked cases use invented acids, so no chemical preparation or experiment is required.
Course topic: Organic Chemistry
Study route and exercise: University Reading List editorial project. How we curate · Sources checked:
Scope and responsibility
For students entering organic chemistry after general chemistry. The route compares Soderberg’s 2019-updated biological text, McMurry’s tenth edition and Clayden’s second edition. It covers a selected reasoning sequence, not every reaction or a laboratory syllabus. Both problems are constructed paper models; numerical pKa inputs are stipulated, not measurements of named substances.
Choose your starting point
I want biological context first
Use Soderberg as the main reading when biochemical examples make the structural ideas easier to connect. Keep a separate list of topics your own course additionally requires.
I need a broad free survey
Use the authorized McMurry web text for the usual two-semester map and selected exercises. Its chapter order is not interchangeable with Clayden’s.
I need a mechanism-led second explanation
Use a legitimate Clayden copy when drawing electron movement and explaining alternatives are your main difficulty. Return to the free route if access or the pace blocks progress.
Compare the three books
Organic Chemistry with a Biological Emphasis
Timothy Soderberg · 2019
Free biological-context spine
- Choose it when
- You want structure and reactivity explained through biological chemistry.
- Use another route when
- Your immediate syllabus requires extensive synthetic coverage or a different assigned problem sequence.
- Selected reading
- Volume I: structure, structure determination, acid–base chemistry and substitution; choose named sections in the 2019 revision.
- Limits and trade-offs
- The author’s emphasis is deliberate, not proof that a biological example needs no chemical foundation. Only selected end-of-chapter solutions are advertised.
Try before choosing
From the acid–base discussion, draw HA+B ⇌ A⁻+BH⁺ with the two electron-pair moves and label each species’ role.
Check your work: Arrows start at an electron pair, not at a positive charge. Atom inventory and net charge remain unchanged; a curved arrow is not an equilibrium arrow.
Organic Chemistry (McMurry)
John E. McMurry · Edition: 10 · 2023
Free comprehensive survey
- Choose it when
- You need the conventional functional-group course map and publicly readable practice.
- Use another route when
- You expect the book alone to establish laboratory competence or replace an assigned advanced text.
- Selected reading
- Tenth edition: 2.9 on pKa predictions, then selected structure/conformation and stereochemistry sections before mechanisms.
- Limits and trade-offs
- OpenStax provides free web/PDF reading under a noncommercial share-alike licence. Free access does not mean unrestricted reuse or a guarantee that every problem has a public full solution.
Try before choosing
Use section 2.9 to predict which side is favoured when the product conjugate acid has a pKa two units higher.
Check your work: State K≈10² under the same-medium idealized convention. This is an equilibrium comparison, not a numerical reaction rate or 100% conversion.
Organic Chemistry
Jonathan Clayden; Nick Greeves; Stuart Warren · Edition: 2 · 2012
Mechanistic comparison companion
- Choose it when
- You want to explain why a proposed electron movement is plausible and compare competing accounts.
- Use another route when
- You only need a brief survey or cannot obtain the selected second edition.
- Selected reading
- Use the second-edition discussions of acidity/basicity, electron movement and mechanism; locate them in your copy rather than borrowing another text’s numbering.
- Limits and trade-offs
- OUP’s companion identifies the authors/edition, but its student resources are password protected. A list of animations or chapter questions is not a promise of open full-book access.
Try before choosing
Explain the same proton-transfer diagram in words, including where the broken bond’s pair ends up; then contrast that explanation with a memorized reagent label.
Check your work: A reader can follow a complete electron/charge account. If the explanation is only “stronger reacts”, return to the structural section before adding new reactions.
Check your preparation
What should I know first?
Lewis structures, formal charge, equilibrium and logarithms from general chemistry. Practise one charge calculation and one pKa difference before using the worked model.
Does a large K identify a fast reaction?
No. K compares equilibrium states under a specified convention; a rate needs kinetic information not supplied here.
Why are structure drawings necessary?
Names and formulas can hide connectivity, charge and stereochemistry. A drawing is an argument that can be checked, not decoration.
Six steps with a concrete output
Outputs marked ready: 0 / 6
These are your own study marks, not an assessment. They are not sent to this site.
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Make a structure ledger
Selected reading: Soderberg Volume I structure; McMurry opening structural sections.
Make this: For three supplied textbook examples, record connectivity, formal charges and the evidence used to identify a functional group.
Check your work: Distinguish a resonance contributor from a different arrangement of atoms; cite the chosen section.
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Track electron pairs
Selected reading: The selected acid–base/electron-movement discussions.
Make this: Draw the generic transfer in the trial and write a sentence for each arrow.
Check your work: No atom or electron pair appears without a source; the final charge sum agrees with the initial sum.
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Separate three questions
Selected reading: McMurry 2.9 and the same topic in the main text.
Make this: Make separate columns for equilibrium direction, equilibrium amount and rate, with an example of evidence needed for each.
Check your work: A pKa comparison does not fill the rate column.
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Solve the constructed balance
Selected reading: The original example below.
Make this: Set up a concentration table and solve for the allowed extent, retaining units.
Check your work: Substitute the result into K and verify both conserved moieties.
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Change the starting mixture
Selected reading: The follow-up below; reread reaction quotient versus equilibrium constant.
Make this: Predict direction before solving, then compare with the first model.
Check your work: K stays the same; Q and the permitted change depend on initial composition.
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Write a transferable explanation
Selected reading: Your three text trials and completed ledgers.
Make this: Write a short account choosing one main text, one specific difficulty it addresses and one remaining limitation.
Check your work: Use a demonstrated task result rather than popularity, price or a claim that one text fits every course.
Worked exercise
An invented proton-transfer equilibrium
For HA+B ⇌ A⁻+BH⁺, stipulate pKa(HA)=4 and pKa(BH⁺)=8 in one common medium. Initially HA and B are each 1.00 mmol/L and both products are zero. Find the equilibrium concentrations, and decide what can be said about rate.
Assumptions
Use an ideal closed, constant-volume paper model with only this reaction, equal activity conventions and K=[A⁻][BH⁺]/([HA][B])=10^(8−4). All values are teaching inputs; no named chemical, apparatus or synthesis is proposed.
- K=10⁴. Let x mmol/L react: HA=B=1−x and A⁻=BH⁺=x, with 0≤x<1. The same concentration reference cancels in this ratio.
- x²/(1−x)²=10⁴ gives x/(1−x)=100, hence x=100/101≈0.99010 mmol/L. Each reactant is 1/101≈0.009901 mmol/L.
- Each conserved HA/A⁻ or B/BH⁺ total remains 1.00 mmol/L. Product charges cancel. Substitution recovers (100)²=10⁴.
Answer and interpretation
Products are each about 0.99010 mmol/L; reactants are each about 0.009901 mmol/L. The equilibrium strongly favours products but is not complete. No numerical or comparative rate follows from these inputs.
Test the result
Check the nonnegative range before accepting a root. Do not interpret pKa difference as a conversion percentage, and do not turn this concentration model into a preparation instruction.
Change an assumption
The same K can initially favour the reverse direction
Keep the same K and idealizations, but start with HA=B=0.0100 mmol/L and A⁻=BH⁺=2.00 mmol/L. Predict the initial direction and solve for the new equilibrium.
- Q=(2/0.01)²=40,000, greater than K=10,000. The net change toward equilibrium is therefore reverse, despite K still being large.
- Let y mmol/L move in reverse: products become 2−y and reactants 0.01+y. Taking the positive ratio gives (2−y)/(0.01+y)=100, so y=1/101≈0.009901.
- Equilibrium reactants are about 0.019901 and products about 1.990099 mmol/L. Each conserved total is 2.0100 mmol/L.
Answer and interpretation
The mixture initially moves in reverse. A product-favoured K does not mean every starting mixture must move forward. The final product/reactant ratio is again 100 for each pair.
Test the result
Compare Q before solving; confirm y lies between zero and 2. Use the new total 2.01 rather than carrying over the old 1.00. No information about how quickly equilibrium is reached was added.
Common mistakes
Equating equilibrium and speed
A favourable balance is not a kinetic mechanism or a clock. Keep the evidence questions separate.
Importing chapter numbers
The three books organize topics differently. Match the selected edition and named topic before taking an assignment.
Confusing free reading with all permissions
Read through official routes; check the stated licence and any restricted companion-resource access separately.
Before moving on
- I can account for atoms, charge and electron-pair movement in the generic transfer.
- I can distinguish Q, K, equilibrium amount and rate using the two constructed mixtures.
- I can justify one text choice with an actual trial result and identify the next topic that my route omits.
Sources and edition checks
Sources checked:
- University of Minnesota Morris: Soderberg Volume I revision and rights
The author and university record identify the two-volume biological emphasis, July 2019 revision, free reading and selected solution resources. The guide uses named topics instead of unverified page ranges.
- OpenStax: tenth-edition dedication and preface
The OpenStax preface verifies the tenth-edition, two-semester functional-group scope, free web/PDF access and CC BY-NC-SA4.0. An official reading entry is restored on the older catalogue record.
- Oxford: Clayden second-edition resources and access
The OUP companion verifies Clayden/Greeves/Warren, second edition and password-protected student extras. It does not establish unrestricted textbook access.
- OpenStax: section2.9 pKa predictions
OpenStax section 2.9 supplies the pKa comparison method; both numerical mixtures and their complete balances were created for this site.
These are proposed study activities, not official course assignments or a claim that every book has been read cover to cover.