Ratio match
The supply ratio has to match the recipe ratio if you want both bins to support the same number of complete batches.
Reactant A packets 10 Reactant B packets 15 A per batch 2 B per batch 3
Concept module
Stoichiometric Ratios and Recipe Batches
Keep one reaction recipe visible so stoichiometric ratios read as complete batches, not detached worksheet proportions.
The simulation shows two reactant supply bins, one product tray, and a recipe card that states how many packets of A and B one full batch needs. A readout card reports the current recipe, the maximum possible batches, which supply is limiting, the actual output, and how much of each reactant is left after the run. The current recipe is 2 A + 3 B -> 1 batch. With 10 A and 15 B, the run can support about 5 full batches. The supplies match the recipe closely, so neither reactant runs out first. At full yield, the actual output reaches the theoretical batch count.
Interactive lab
Stoichiometry recipe bench
Keep the recipe card, the two reactant supplies, and the actual product output on one bench so ratios, limiting packets, and yield never drift into detached worksheet algebra.
Controls
Change how many A packets the current run starts with.
Change how many B packets the current run starts with.
Set how much A one full recipe batch consumes.
Set how much B one full recipe batch consumes.
More tools
Secondary controls, alternate presets, and less-used toggles stay nearby without crowding the main bench.
Show
More tools
Secondary controls, alternate presets, and less-used toggles stay nearby without crowding the main bench.
Keep this at 100% here so the recipe ratio is the main story.
More presets
Presets
Predict -> manipulate -> observe
Keep the active prompt next to the controls so each change has an immediate visible consequence.
ObservationPrompt 1 of 2
A matched supply ratio makes the two cap lines land on the same batch count.
Graphs
Switch graph views without breaking the live stage and time link.
Possible batches vs A supply
Watch the possible batch count rise until the fixed B supply becomes the cap.
reactant A packets: 2 to 18recipe batches: 0 to 8
Possible batchesB supply cap
Equation map
See each variable before you move it.
Select a symbol to highlight the matching control and the graph or overlay it most directly changes.
Reactant A packets
10Changes how many A packets the recipe can spend on complete batches.
Graph: Possible batches vs A supplyOverlay: Recipe cardOverlay: Limiting cue
Equations in play
Choose an equation to sync the active symbol, control highlight, and related graph mapping.
More tools
Detailed noticing prompts, guided overlays, and challenge tasks stay available without taking over the main bench.
Hide
More tools
Detailed noticing prompts, guided overlays, and challenge tasks stay available without taking over the main bench.
What to notice
Keep the recipe card and one batch graph in view together.
ObservationPrompt 1 of 2
Graph: Possible batches vs A supply
A matched supply ratio makes the two cap lines land on the same batch count.
Control: Reactant A packetsControl: Reactant B packetsControl: A per batchControl: B per batchGraph: Possible batches vs A supplyGraph: Possible batches vs B supplyOverlay: Recipe cardOverlay: Limiting cueEquationEquation
Guided overlays
Focus one overlay at a time to see what it represents and what to notice in the live motion.
3 visible
Overlay focus
Recipe card
Keep the reaction recipe visible while the supply bins change.
What to notice
- The same supplies tell a different story when the recipe card changes.
Why it matters
It keeps stoichiometric ratios attached to one visible batch recipe instead of detached proportion rules.
Control: A per batchControl: B per batchGraph: Possible batches vs A supplyGraph: Possible batches vs B supplyEquationEquation
Challenge mode
Keep the recipe honest: build a matched run where the batch cap lands on both supplies together.
0/1 solved
ConditionCore
3 of 8 checks
Build the matched 3:2 run
Set the bench to a 3 A + 2 B recipe with supplies that still finish four full batches together.
Graph-linkedGuided start2 hints
Pending
Open the Possible batches vs B supply graph.
Possible batches vs A supplyMatched
Keep the Recipe card visible.
OnMatched
Keep the Limiting cue visible.
OnPending
Set A per batch to 3.
2Pending
Set B per batch to 2.
3Pending
Land A at 12 packets.
10Pending
Land B at 8 packets.
15Matched
Keep yield at 100% so only the recipe ratio is being tested.
100The checklist updates from the live simulation state, active graph, overlays, inspect time, and compare setup.
The current recipe is 2 A + 3 B -> 1 batch. With 10 A and 15 B, the run can support about 5 full batches. The supplies match the recipe closely, so neither reactant runs out first. At full yield, the actual output reaches the theoretical batch count.
Equation detailsDeeper interpretation, notes, and worked variable context.
Batch cap
A full reaction run can only make as many batches as the tighter recipe-supported supply allows.
Reactant A packets 10 Reactant B packets 15 A per batch 2 B per batch 3
Progress
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Stable links
Starter track
Step 1 of 30 / 3 completeStoichiometry and Yield
Next after this: Limiting Reagent and Leftover Reactants.
1. Stoichiometric Ratios and Recipe Batches2. Limiting Reagent and Leftover Reactants3. Percent Yield and Reaction Extent
This concept is the track start.
Short explanation
What the system is doing
Stoichiometric ratios become easier to trust when one recipe card stays visible beside the actual supply bins. This bench keeps the recipe, the two reactant supplies, and the finished product tray on one run so the idea of a full batch never turns into detached worksheet algebra.
The key move is to count complete recipe batches, not isolated particles. If the recipe says 2 A plus 3 B, then every finished batch has to spend those packets together.
Key ideas
01A stoichiometric ratio is a recipe for one full reaction batch, not just a pair of unrelated numbers.
02Matching the supply ratio to the recipe ratio keeps either reactant from running out first.
03Changing the recipe card changes how many full batches the same supplies can support.
Worked example
Read the full frozen walkthrough.
Frozen walkthrough
Use the recipe bench rather than a detached proportion drill.
Live worked examples are available on Premium. You can still read the full frozen walkthrough on the free tier.
View plansFrozen valuesUsing frozen parameters
How many full batches can the matched 2 A + 3 B setup make?
Reactant A packets
reactantAAmountValue
Reactant B packets
reactantBAmountValue
A per batch
recipeAValue
1. Read one complete batch from the recipe card
One full batch spends 2 packets of A and 3 packets of B together.
2. Count how many copies of that recipe fit
The matched setup contains 10 A and 15 B, which is five copies of the same 2:3 recipe.
3. Read the product tray as finished batches
Because both supplies scale together, the bench can finish five full batches without either side capping the run early.
Batch count
full batches
When the supply ratio matches the recipe ratio, the reaction can keep finishing full batches until both bins empty together.
Common misconception
If one reactant has the larger number written next to it, that must mean it always makes more product.
Product comes from complete recipe batches, not from whichever supply has the larger raw count.
The supply ratio only works cleanly when it matches the recipe ratio shown on the same bench.
Mini challenge
Keep a matched recipe where neither reactant caps the run first.
Prediction prompt
Decide whether you need to change the supplies, the recipe card, or both before you touch the sliders.
Check your reasoning
You need the supply ratio to match the recipe ratio shown on the bench.
That keeps the same number of full recipe batches available from both bins instead of letting one reactant run out early.
Quick test
Misconception check
Question 1 of 2
Answer from the recipe bench, not from memorized cross-multiplication.
Which statement is the cleanest stoichiometric reading?
Choose one answer to reveal feedback, then test the idea in the live system if a guided example is available.
Accessible description
The simulation shows two reactant supply bins, one product tray, and a recipe card that states how many packets of A and B one full batch needs.
A readout card reports the current recipe, the maximum possible batches, which supply is limiting, the actual output, and how much of each reactant is left after the run.
Graph summary
One graph scans possible batches against the A supply, a second scans possible batches against the B supply, and a third compares actual product with the theoretical product as percent yield changes.
Graph hover, compare mode, and the shared overlays stay tied to the same recipe bench instead of opening a separate chemistry-only view.
Carry the recipe into the next reaction step
Keep moving through the concept map.
These suggestions come from the concept registry, so the reason label reflects either curated guidance or the fallback progression logic.
Find the limiting sideStoichiometry and Yield
Limiting Reagent and Leftover Reactants
Use one recipe bench to see which reactant caps the output first and why the other reactant can remain in excess.
Compare actual vs theoreticalStoichiometry and Yield
Percent Yield and Reaction Extent
Compare actual output with the same theoretical recipe cap so percent yield stays visual and honest on one shared bench.
Useful comparisonRates and Equilibrium
Reaction Rate / Collision Theory
Keep one chemistry box visible so temperature, concentration, activation threshold, and catalysts can be read as changes in successful collisions instead of chemistry slogans.