Learn Fifty-eight original lessons across six categories and final synthesis are implemented. The two synthesis destinations complete the finite 58-destination authored plan; independent full-course scientific and scope review passed. Actual learner performance and external practical, technical and institutional gates remain separate.
This is the course outline. Open a unit to choose a lesson; every lesson opens on its own page. Explanations and experiments live inside those lesson pages.
Preparation: General Chemistry I or equivalent amount, bonding and energy reasoning. Algebra, logarithms and dimensional ratios are introduced where used; no prior lesson completion is required to open this category.
Course outcome: Reconcile solution/activity, kinetic, equilibrium, acid/base and coupled-solubility evidence; audit thermodynamic, electrochemical, nuclear and coordination models; design independent constraints and finite-process arguments without overclaiming identity, rate, usable work or practical competence.
All lessons are directly accessible. Reused foundation explanations are identified where relevant; completing a different course does not award this course's evidence. The 58 registered lessons keep separate predictions, captures, practice responses and reflections.
Analyze composition and activity conventions, compare ideal/nonideal vapor and gas-dissolution constraints, and distinguish effective particle evidence from a unique chemical explanation.
Hold solute mass6 g while comparing densities1.00 and1.20. Derive all four concentration measures; then hold density and double solute mass. Explain why neither comparison authorizes adding pure component volumes.
Compare gamma .5,1 and1.5 at c=.08 M. Separate RT ln(c/c°) and RT ln gamma; construct two distinct concentration/gamma pairs giving equal activity.
Compare xA=.3,.5,.7 at parameter0 and1. Record each partial pressure, total and vapor composition. Identify which changes are due to composition versus the supplied activity correction.
Compare(200 kPa,.20) with(100 kPa,.40), then compare fixed total pressure at two fractions. Retain partial pressure and equilibrium concentration; identify the held-fixed temperature and solvent.
Compare m=.10,i=2 with m=.20,i=1. Then hold m while varying i. Retain both shifts and their ratio; explain which hypotheses these comparisons cannot distinguish.
Compare AB at alpha1,AB2 at alpha.5 and monomer pairing at alpha.5. Audit species and conserved original units before using a freezing shift.
Compare(4,1),(1,4) and(3,3)mM. Track the sign of required left-minus-right pressure and distinguish initial flow direction from an evolving finite-volume state.
Hold depression.20 K while comparing factors.5,1,1.5. Derive conservative endpoints from the stated mass, solvent and temperature bounds. Predict a boiling shift as a held-out consistency check.
Infer and challenge empirical rates using controlled, integrated and temperature evidence; reconcile competing mechanism inventories without mistaking fit for unique causation.
Compare durations 1, 2 and 4 s from the same start. Normalize A disappearance by 2, compare B appearance, and distinguish interval average from the start and midpoint derivatives.
Compare base (1,1), A-only (2,1), B-only (1,2) and combined (2,2) factors. Derive exponents from rate ratios and check the combined held-out prediction.
Compare three orders at A0=1 M, then double A0 for each. Predict half-life scaling and explicitly locate the zero-order depletion boundary.
For each generating order, compare candidate endpoint fits and raw-scale held-out residuals. Perturb only the final reading by+.02 M and retain how the inferred constants and residual patterns change.
Hold k=.10 and compare backgrounds 0, 10 and 20. Calculate raw and corrected two-time constants. Then vary k at a fixed background and explain why two raw readings cannot identify k, baseline and an unknown initial reactive amplitude together. Contrast the independently known amplitude 100: a t=0 reading gives B=S(0)−100, after which the later reading identifies k.
At fixed barrier compare280,300 and320 K. Then compare barriers40 and60 kJ/mol at300 K with A fixed. Derive the inverse-temperature slope and name the assumptions that allow a two-temperature inference.
Compare A=.1,.5,1.0 M at Kd=.5 and then Kd=.1. Derive free/bound catalyst amounts and compare the exact rate with the low-A approximation and saturation ceiling.
Compare(.1,.4),(.2,.3) and(.4,.1). Retain the identical total-decay cases and distinct product curves, then check A+B+C conservation at several times.
Compare(.2,.2),(.2,.4) and(.4,.2). Retain A,B,C profiles, the peak time and conserved total; explain how formation and consumption compete at the peak.
Solve dimensionless equilibrium relations with feasible component balances, test approximation and phase-existence assumptions, and distinguish kinetic relaxation or calibration cancellation from equilibrium evidence.
Vary A and the prescribed common gamma separately. Compute each normalized activity before Q; locate the direction boundary and explain why Q−K is not a rate.
Derive each transformation by multiplying or inverting activity quotients. Compare formal coefficient scaling with a real concentration perturbation.
Bracket x using the smaller initial reactant. Compare unequal inventories, recover Q, and check A+C and B+C separately rather than conserving the total molecule count.
Compare volume settings at one Kp. Compute both partial pressures from final amounts, recover the normalized quotient and contrast the immediate dilution with final relaxation.
Vary K2 at fixed K1, calculate all three amounts from one total, and verify both local ratios and the overall constant.
Vary analytical concentration at fixed Kd. Retain exact and approximate roots, x/C and relative output error; identify a case where the approximation creates more product than the supply permits.
Cross the n=.20V boundary. Record dissolved inventory, surviving solid and aqueous activity; distinguish undersaturated, saturated-with-solid and exact-boundary states.
Compare multiplier settings from two starting compositions. Verify the common endpoint, matching nonzero equilibrium rates and different approach speeds.
Change the shared scale, calculate ratio bounds from separate channel errors, then predict a held-out .60 M total. Identify an independent observation needed to test response selectivity or time stability.
Derive acid/base states from compatible constants, water, mass and charge balances; distinguish conditional distributions, finite buffer reserves, local capacity, stoichiometric equivalence and observed endpoint criteria.
Vary the donor and product conjugate-acid constants separately. Write the two ionization equations whose quotient gives K, then distinguish proton transfer from a non-proton Lewis association.
Compare three supplied pKw values at zero offset, then move one pH unit in each direction. Recover hydronium/hydroxide concentrations, product and ratio.
Vary analytical concentration across the water scale and compare exact versus neglect-water pH. Verify h−OH=C and reject the negative quadratic root.
Compare total concentrations at fixed Ka. Recover HA+A−=C, h=OH+A− and the quotient; quantify the shortcut error rather than assuming negligible depletion.
Switch the reactive ion while keeping concentration and parent pK fixed. Derive KaKb=Kw, identify the inert counterion and compare acidic/basic pH around neutrality.
Scan imposed pH and verify normalized fractions. Change total family concentration without changing the imposed pH, then identify the omitted reservoir that maintains charge balance.
Compare additions below, at and above the reserve. Preserve the stoichiometric table, exact equilibrium species and the domain where the HH ratio remains meaningful.
Hold the pH offset fixed while scaling total concentration, then scan pH to find the capacity maximum. Separate buffer-family and water terms, and reject large-addition claims from a local derivative.
Compare initial, half-equivalence, equivalence and excess-base points. Retain dilution and charge residuals; contrast the strong-acid curve with identical starting equivalents.
Change indicator pK and the declared transition half-width. Map lower/mid/upper pH thresholds to volume and compare with equivalence; retain interval asymmetry and the trace-indicator assumption.
Reconcile free-ion products with dilution, phase and finite inventories; derive selective-precipitation feasibility and coupled ligand/proton effects without confusing total assays with free species.
Compare all three charge-balanced formula types. Write each dissolution equation, normalize ion activities and distinguish formula-unit amount from each ion concentration.
Vary common-ion supply at gamma1, then vary gamma at a fixed supply. Recover activities and product rather than inferring Ksp from bare total amounts.
Calculate combined volume first, then Q and the feasible precipitated extent. Retain final free ions, solid amount and an explanation of why the constraint curve is not a time trace.
Compare second-metal inventories .5,1 and2 mM. Calculate the99% first-metal threshold and second-metal onset; distinguish positive-width, equality-only and impossible windows. Then design a robust interval with M1=.001±.0001 M and M2=.0005±.00005 M, test controlled X=.00015 M, and contrast M2=.001±.0001 M using worst-case endpoints.
Vary total ligand through the metal amount and vary beta. Recover both free inventories, compare the excess-ligand approximation and reject any complex amount above either supply.
Vary reservoir-controlled free ligand at two common-ion levels. Verify free-ion Ksp, total metal partition and the ligand-reservoir boundary rather than substituting total metal into Ksp.
Compare pH with pKa at fixed constants, recover metal and anion-family totals and free-ion Ksp, then state the reservoir that maintains the imposed condition.
Vary complexation factor and common gain separately. Compare total and free products, propagate independent2%/3% reading bounds and identify the external information needed to infer true Ksp.
Connect constrained entropy and standard/nonstandard Gibbs energy with equilibrium and signed electrochemical work; audit finite charge and nuclear ensembles; distinguish formal coordination bookkeeping, orbital-model predictions and actual spectral evidence.
Compare left populations at fixed N, then vary N. Retain multiplicity, probability and the limited entropy contribution rather than claiming a full real-gas entropy.
Vary the hot temperature and cold heat capacity. First close energy, then evaluate both entropy changes through their state-function expressions; reject trial final temperatures that violate isolation.
Construct products-minus-reactants entropy, vary temperature and enthalpy, and locate the conditional sign-change point while stating the omitted heat-capacity corrections.
Compare Q below, at and above the calculated K using the continuous equation. Distinguish the local reaction driving force from a finite reversible work budget.
Compare endothermic, zero and exothermic enthalpies; infer the inverse-temperature slope and test the stated300 K reference.
Vary Q at fixed E° and then E° at fixed Q. Track signed potential, ΔrG and the equilibrium quotient rather than treating voltage as an amount of energy.
Compare unequal, equal and reversed activities. Identify oxidation/reduction sides and ionic versus electronic paths while retaining the neglected junction-potential assumption.
Vary current and duration, close desired plus competing charge, convert through F and the electron coefficient, and verify remaining initial metal inventory.
Compare currents at the same elapsed time, close charge/capacity and all energy terms, and identify the exact capacity-exhaustion endpoint.
Compare pure and mixed initial populations, then separate lambda-weighted activity from remaining count and background-adjusted detected rate.
Compare all four formal ligand sets for ironII/III. Reconstruct complex charge, d count and donor count, then distinguish cis/trans placement from mirror-image possibilities.
Compare d4–d7 at weak, equal and strong splitting. Retain orbital occupations, tied-energy unpaired ranges and the gap wavelength without claiming that every matching photon is an allowed transition.
Design an independently constrained sample argument and reconcile finite composition, kinetics, thermodynamic availability and hypothetical charge without double counting.
Retain two compatible gain hypotheses, freeze a six-of-eight virtual mL allocation and predict an electrode result before revealing it. Explain why a ratio is robust to common multiplicative gain but not an additive offset.
Compare two K values at the same total rate coefficient and two initial totals at fixed K. Retain concentration, extent, heat, Gibbs-excess decrease and hypothetical charge ceilings with their distinct assumptions.
Keep predictions before comparison, complete raw records and units, explain competing models and test a changed case. Supplied and simulated data are labeled in each lesson. A saved notebook is not proof of experimental technique or correct reasoning.
Evidence to retain: Freeze two compatible assay hypotheses and a6-of8 virtual mL allocation before reference disclosure. Retain independent-reference inversion and a withheld check. Separately compare finite reaction endpoint, relaxation time, heat, Gibbs excess and charge ceilings across changed K and total inventory.
Boundary: Original supplied/simulated packets only. No real sample consumption, electrode operation, heat transfer or work-producing device. Calibration and practical identity remain conditional.
Evidence to retain: Retain multiplicity and restricted entropy, energy-balanced thermal endpoints, standard entropy/enthalpy ledger, Q-versus-K driving forces and a van’t Hoff versus Arrhenius distinction with changed conditions.
Boundary: Finite synthetic arrangements and constant-property thermal/reaction models. No actual heat exchange, calorimetry or universal extrapolation across phases.
Evidence to retain: Preserve reaction/electron normalization, Nernst direction and concentration-cell polarity; close current-efficiency product and finite-capacity energy accounts, including internal conversion and omitted practical losses.
Boundary: Fictional ideal electrode/charge packets, not devices or operating specifications. No wiring, electrolysis, charging, corrosion treatment or physical electrical activity.
Evidence to retain: Separate identity/mass-energy conservation, lambda-weighted mixed activity and detector response; reconstruct oxidation/ligand/donor ledgers and test paired/unpaired orbital minima with a retained degenerate boundary.
Boundary: Synthetic ensembles, formal complexes and a bounded crystal-field/pairing model. No radioactive source, irradiation, actual synthesis, observed stability, magnetic measurement or color identification is certified.
Evidence to retain: Retain charge-balanced dissolution equations and ion counts, a common-ion/activity contrast, mixed-volume depletion root and positive/equality-only/absent selectivity windows for a defined removal target.
Boundary: Hypothetical ideal or prescribed-coefficient states; externally controlled free anion is not added total reagent. No physical precipitation, mixing or separation.
Evidence to retain: Close both finite-ligand inventories, contrast controlled-free-ligand and imposed-pH dissolution, then compare total/free assay products and bounds with a shared calibration alternative.
Boundary: External reservoirs are explicit. Filtering or measuring total dissolved metal is not claimed to isolate free ions; intervals are conditional bounds, not empirical confidence or true-K certification.
Evidence to retain: Retain proton-transfer algebra, temperature-dependent neutrality, dilute strong-acid and weak-acid balance audits, reactive-salt identification and normalized conditional diprotic species. Use a changed analytical concentration and identify when an external reservoir supplies missing charge.
Boundary: Ideal fictional aqueous packets with explicit inert ions and water constants. Conditional pH is not a predicted pure-acid pH; no chemicals or physical acid/base procedures.
Evidence to retain: Freeze finite proton-transfer inventories and compare exact equilibrium; distinguish equal pH ratios from differential capacities; retain a full dilution/charge titration curve and map indicator-window bounds to volume without calling them measured confidence.
Boundary: Supplied concentration conventions and trace indicator. No pH meter, color observation, titration or practical technique is performed or certified.
Evidence to retain: Retain activity-normalized quotients, exact reaction transformations, a root feasibility audit, disturbed versus relaxed gas partial pressures and a shared coupled-network inventory.
Boundary: Fictional ideal or explicitly prescribed-activity packets, not measured chemical constants. No gas vessel or actual mixture is manipulated.
Evidence to retain: Compare exact and approximate dissociation roots; cross a finite-solid existence boundary; verify unchanged endpoints with altered relaxation times; propagate bounded channel errors into a changed-inventory prediction.
Boundary: Concentration-form Kd is explicitly distinct from dimensionless K. Supplied bounded errors are not confidence intervals, and no physical phase or real catalyst is observed.
Evidence to retain: Retain stoichiometric-normalized rates, controlled exponent contrasts, half-life scaling, endpoint fits with withheld raw residuals and baseline-corrected versus uncorrected signal inference.
Boundary: Synthetic constant-volume observations and declared optical response. No chemical reaction or instrument calibration was performed.
Evidence to retain: Derive an inverse-temperature ratio, conserve free/bound catalyst, exhibit equal-disappearance/different-product branches, and test an intermediate peak including equal-rate limits.
Boundary: Supplied fixed-mechanism models and fictional isomer networks. No real catalyst, reactive material or heating procedure; compatibility is not unique mechanism proof.
Evidence to retain: Retain contrasting density/concentration denominators, equal-activity alternatives, separate liquid/vapor compositions and equal-partial-pressure Henry packets. Predict each change before capturing and explain which assumptions an observation can actually test.
Boundary: Original supplied properties and activity hypotheses; no preparation, heating, distillation or pressurized gas activity.
Evidence to retain: Preserve freezing/boiling shift consistency, dissociation versus association species inventories, signed two-compartment osmotic differences and conservative apparent-mass endpoints. Construct competing explanations that fit the same observation.
Boundary: Ideal-dilute fixed-condition models, not measured dissociation, membrane physiology, molecular identity or clinical guidance.
Open the retained response and project workspaces. Practice, saved work and independently reviewed proficiency remain separate.
These 15 course-specific public tasks are practice, not a secure examination. Each retains up to three immutable written responses, known feedback exposure before each response, and human rubric critiques. Drafts remain editable. No text-length check or self-reported review certifies correctness, independence, laboratory skill or mastery.
Two zero-offset assays share an unknown positive gain and report total signal .060 and free signal .020. An independently standardized ideal two-electron electrode establishes free concentration .008 M. Infer total/free ratio, gain and total concentration. Compare a withheld total interval .0235–.0245 M. If a common additive offset were unknown instead, identify the failed inference. Explain why a ligand reservoir ratio1+β[L] does not independently identify both β and[L]. Allocate2 mL to each assay,1 to electrode and1 to withheld check from8 mL.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
An ideal A⇌B packet initially contains .040 M A in .050 L at298.15 K, K1, kf+kr=.100 s⁻¹ and supplied reaction enthalpy−20 kJ/mol. Find equilibrium B, kf/kr individually, B after10 s, extent, reaction heat for the constant-pressure path with onlyPV work, and time/fraction of initial A converted at90% of equilibrium B. Describe how to calculate a finite reversible non-expansion-work bound and why the observed relaxation does not establish delivered work or a cell voltage.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
Ten equally weighted independent labeled particles occupy either equal compartment. Compare multiplicity252 for the5/5 macrostate with1 for a specified all-left state: find probability of the former and configurational entropy difference. Separately isolated heat capacities100 and50 J/K begin450 and300 K: find final temperature, signed energy changes and total entropy. A separate reaction has standard enthalpy−25 kJ/mol and entropy−100 J/(mol K), assumed constant: compare ΔrG° at250 and350 K. At298.15 K a different reaction has ΔrG°0 but Q.10: infer current ΔrG, K and favored direction. Explain why neither a rate nor arbitrary finite work follows.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
A two-electron cell reaction has reversible E=.0800 V. Find ΔrG per written mole of reaction and describe what changes when all reaction coefficients double. For identical M²+/M electrodes at298.15 K, right activity is ten times left: find signed right-minus-left E and galvanic cathode. A separate three-electron reduction receives900 C with current efficiency .80: find product moles. A fictional cell of emf1.50 V and internal resistance .20 ohm discharges .50 A for20 min from1 Ah capacity: close remaining charge, external energy and internal conversion. Name at least two omitted real-cell limitations.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
A pure parent ensemble has12000 nuclei, half-life6 h and stable daughters: find surviving parents and activity after12 h, in decays/h and Bq. With detector efficiency .80 and independent50 counts/h background, find expected indicated rate. A separate fictional reaction loses .00200 u of consistently defined rest mass: infer Q using931.494 MeV/u and state why this does not establish a reaction rate. For formal ironIII with three neutral bidentate en ligands, find complex charge, ligand count, coordination number and d count. For ideal octahedral d6 with splitting3 eV and pair cost2 eV, identify the lower-state occupancy and unpaired count; compare the equality boundary and explain why a2 eV optical gap does not uniquely predict observed color.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
For fictional ideal M2X with dimensionless Ksp4×10⁻¹² and c°1 M, find formula solubility and both ion concentrations. Separately combine10.0 mL .001 M M+ with30.0 mL .001 M X−, Ksp10⁻⁸: calculate the immediate diluted product, set the feasible precipitation equation and find the equilibrium extent and solid amount. A separate two-metal system begins M1=.001 M and M2=.002 M with Ksp1=10⁻⁹,Ksp2=10⁻⁷. Can externally controlled free X achieve99% M1 removal before M2 starts precipitating? Explain why this is not a physical separation guarantee.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
A fictional1:1 metal/ligand packet has Mtotal=.001 M,Ltotal=.002 M and concentration beta10⁴ M⁻¹: solve bound complex with both inventories, not a fixed free ligand assumption. A distinct excess-solid MX packet has Ksp10⁻⁸, the same beta and externally maintained free ligand .001 M with no common anion: find total and free metal. A third protonation-coupled solid has Ksp10⁻⁸ and pKa5 at imposed pH3: find total solubility and explain the reservoir assumption. Finally free M=X=10⁻⁴ M but total/free metal factor4 and shared assay gain.90: compare naive total-metal and indicated free-ion products, and identify two independent checks needed before inferring true Ksp.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
For HA+B⇌A−+BH+, donor pKa is 6 and product conjugate-acid pKa is 4 under matching conventions. Infer K and explain why this does not specify a rate. Separately an ideal water packet has pKw 13 and pH5.5: find pOH and the hydronium/hydroxide ratio. At pKw 14, a 10⁻⁷ M completely dissociated monoprotonic acid with inert counteranion is supplied: solve hydronium including water and explain why h=C fails. Finally a diprotic family has pKa 1=3,pKa 2=7, externally imposed pH7 and total .0200 M: find all fractions and explain why they do not establish the pH of pure H2A.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
A fictional 1 L buffer at pKa 5 starts with 4 mmol each HA and sodium A. Add1 mmol strong acid at negligible volume change: find nominal postreaction amounts and HH pH, then state the exact charge relation that would refine it. A separate buffer at pH=pKa has total .0400 M: find its family differential capacity and a local pH-change estimate for .00100 mol/L added base, using ln10=2.302585. A separate25.0 mL .100 M weak monoprotic acid receives35.0 mL .100 M monobasic strong base: estimate pH from excess base at pKw 14 and retain dilution. For a trace indicator pKind 8, find form ratios at pH7.5 and 8.5 and explain why a symmetric pH window need not yield a symmetric volume interval or an experimental confidence interval.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
For ideal A+B⇌C with c°=1 M, A0=1.20 M, B0=.80 M, C0=0 and K=5, find the feasible concentration extent and recover component balances and Q. Separately, X⇌Y has K1=3 and Y⇌Z has K2=2: derive the constant for 2Z⇌2X and all X/Y/Z concentrations at total .80 M. For an ideal A2⇌2A gas initially at equilibrium, compare the immediate Q after doubling volume at unchanged temperature and the favored subsequent direction. Distinguish that immediate state from final equilibrium.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
For fictional AB⇌A+B, C=.020 M and concentration-form Kd=.010 M, solve x exactly and compare √(KdC). For a different pure solid with saturation .20 M, put .25 mol into1.50 L: determine concentration and remaining solid. A separate first-order reversible pair has kf=.60, kr=.20 s⁻¹ and total1 M: find equilibrium A/B, opposing rates and the time constant before and after doubling both rate constants. Finally a calibrated isomer pair indicates A=.20,B=.60 M with independent ±.01 M bounds. Bound K=B/A and predict B for a held-out total .50 M; explain which effects a shared positive gain would and would not cancel.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
For3X→2Y, measured X disappearance is.120 M/s. Infer normalized rate and Y appearance. A separate initial-rate packet triples when A triples alone and quadruples when B doubles alone: infer orders, overall order and k units when normalized rate is M/s. Another packet has A0=1.00,A4=.50,A8=.25 M. Infer the first-order constant and predict A12; compare the intermediate4 s prediction of a zero-order model fitted only at0 and8s. Explain why a constant positive signal background can invalidate a raw log-slope interpretation.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
A constant-parameter Arrhenius packet doubles k from300 to310 K. Infer Ea with R = 8.314 and state why this is not a reaction enthalpy or equilibrium constant. A separate catalyst-binding packet has Ctotal=.0200 M,kcat3.00 s⁻¹,Kd=.20 M and free A=.60 M: derive bound/free catalyst and rate. A separate parallel isomer network has total disappearance constant.60 s⁻¹ and calibrated B fraction.25 of reacted amount: infer branch constants. Finally a consecutive isomer network has k1=.10,k2=.20 s⁻¹: find intermediate peak time and A/B/C amounts at that time. Explain why a transient peak alone does not prove an obligatory intermediate.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
A fictional6.00 g nonelectrolyte of molar mass75.0 g/mol dissolves in120.0 g solvent of molar mass18.0 g/mol; solution density is1.05 g/mL. Find mass fraction, molality, molarity and solute mole fraction. Separately a neutral solute at.040 M has gamma1.25 on a1 M standard: find activity and compare a.050 M ideal packet. In a distinct ideal volatile mixture, pure vapor pressures are80 and30 kPa and liquid A fraction.40: find partial pressures, total pressure and vapor A fraction. Explain why these three packets cannot silently be treated as one substance.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
At analytical.150 mol/kg, compare complete AB dissociation with AB2 dissociation fraction.50 under ideal species counting. Find freezing and boiling shifts using Kf1.86 and Kb.512. Separately ideal impermeant solute at298 K is5 mM left and2 mM right; infer the balancing left-minus-right pressure using R8.314 kPa L/(mol K) and initial solvent direction at equal pressure. A separate freezing packet uses2.000±.020 g solute,.2000±.0020 kg solvent and depression.250±.005 K. Infer nominal and bounded molar mass assuming i=1; explain how i=.5 and a boiling measurement change identifiability.
Include calculations with units, source or dataset provenance, assumptions, competing explanations and limitations as relevant. The draft is saved but is not a locked response until submitted.
0/3 responses retained. No recorded feedback exposure for this task version. Earlier versions may already be familiar. Public inspectability still prevents certification of unfamiliarity.
Reviewer identity and role are declarations, not authenticated credentials. Unsaved review fields below are lost on navigation. Review every criterion with an exact quotation, calculation or evidence citation and a next step.
Extend the retained category report into a six-category dossier. Resolve a fictional unknown sample only to the level justified by independent evidence; connect rate, equilibrium and thermodynamic limits without pretending supplied data are measured. Version1 category reports remain archived by the retained-evidence workflow.
Use total/free signals .040/.010 with unknown common gain and zero offsets. Propose two compatible concentration pairs. Allocate6 of8 virtual mL across total/free/reference/withheld packets before requesting the reference. Identify a solution/particle-factor ambiguity and a kinetic offset or mechanism ambiguity in separate preserved category records.
Evidence to retain: Dated first predictions, allocation, two numerical alternatives, declared prior exposure and source/modality for each packet.
Use a separately calibrated electrode free concentration .005 M, infer total and gain and check a withheld .0195–.0205 M total interval. Add an acid/base charge-balance record, a finite-solid or complexation record and a reaction Q/K versus rate comparison from distinct category investigations. Show units and identify observations reused rather than independent.
Evidence to retain: Reference assumptions, calculations, feasible inventories, bounds, contradictory alternatives and explicit limits on unique chemical identity.
For the supplied A⇌B synthesis recipe choose changed total and K, predict equilibrium and timed conversion, and retain extent/heat/Gibbs/charge accounts separately. Add one nuclear ensemble and one coordination orbital-model evidence record, distinguishing conservation/model support from actual material identity.
Evidence to retain: Before-result predictions, contrasting saved recipes, endpoint/path comparison and no double-counting statement; nuclear/coordination entries remain virtual.
Submit the first full dossier before rubric review. Retain criterion-linked critique and a separate revision. A reviewer freezes new signals, one altered calibration assumption, changed K/rate and a withheld constraint before a new independent response; record all help and prior exposure.
Evidence to retain: Immutable first report, self-reported reviewer role, critique, revision, distinct frozen assignment and response. Public examples and self-report are not verified unfamiliar performance.
Retain raw-data identifiers, provenance, units, prior predictions, methods, calculations, competing explanations and safety boundaries. State explicitly when data are simulated, supplied or genuinely observed. This saved text cannot verify a real experiment; do not invent measurements or completed supervised work. Maximum 12,000 characters; retain larger evidence files separately and cite them.
A nonempty report is only a saved submission. First and revised reports remain separate and cannot be overwritten. A critique of the first report is required before retaining one revision.
A new reviewer-assigned packet must change numerical data AND a calibration, inventory or model assumption, not merely repeat public questions. Preserve assignment before response, exposure/assistance declaration and uncertainty. Real supervised laboratory technique requires separate observed evidence.
A human must supply the actual new task, evidence and conditions before the learner responds. The transfer-direction text is not itself an unseen assessment. Use the retained assignment form after the first project; exposed public task identifier: expanded-public:college-chemistry2.
Science backups preserve each course's separate responses, exposure, rubric reviews and project history. Older backups do not reset attempts or erase known exposure. Divergent same-version immutable responses and incompatible same-version project histories are rejected rather than silently replaced; preserve both files for review.
Original LearnAI explanations and tasks use the references for scientific scope. Any attributed dataset or image has its own declared provenance. Laboratory or field activity requires an appropriate educator-approved protocol; no hazardous real-world operation is required by the guided path.
Science work is stored locally in this browser, separately from mathematics and AI. It does not sync automatically. Use this science-only backup; this checkout's older all-subject export does not include science.
A legacy file is available only when the complete snapshot fits the 36 MB limit. For larger snapshots, prepare a complete file set below; never discard notebooks to make a smaller file.
Matching imported notebook drafts replace their current drafts. Omitted lessons and known first attempts remain. Export your current work first if you want to retain both drafts.
A file set can hold more work than one science file. Keep its manifest and every part together. Each file is limited to 36 MB. This format needs this version of LearnAI or a compatible newer version; older versions can use only the legacy single-file backup above.
The set includes every saved science course and global continuation at this moment. Later edits need a new export. A conflicting tab exports its own visible work, which may differ from saved work in another tab.
0 file(s) selected. File order and filenames do not determine identity. Missing, changed or conflicting parts block the entire restore; no good part is applied by itself.
Science storage: loading. No account or remote computation is required.