Chemistry with receipts.

Chemical Bench is not pretending to be an unlimited industrial chemistry engine. It is a classroom model with transparent data packs, visible assumptions, and honest scope messages.

Why this matters

Students can mix, observe, and explain in the browser, while teachers and districts can review exactly what Atomency calculates locally before official classroom adoption.

Modeled now

Dilution and concentration preparation
Strong acid/base neutralization
Weak acid/base and buffer approximations
Ksp and solubility-rule precipitation
Carbonate, bicarbonate, sulfite, and ammonium/base gas-evidence models
Indicator colors with pH-range explanations, conductivity, and heat estimates
Curated redox: acidic permanganate with iron(II)

Data packs

Not claimed

Not intended for professional laboratory or industrial chemistry analysis
No arbitrary organic reaction prediction
No hazardous-real-lab permission system
No required student accounts or server-side student records for core use
No fake result when a mechanism is missing

Supported examples.

These are designed to work from an approved hosted or static deployment without requiring a separate hosted chemistry service.

Investigation	What students see	Calculation basis
HCl + NaOH	pH moves toward neutral, heat pulse, limiting reagent	H+ + OH- stoichiometry and classroom enthalpy estimate
AgNO3 + NaCl	White AgCl precipitate and remaining ions	Ksp/solubility rule with mole balance and precipitate mass
CaCl2 + Na2CO3	White CaCO3 precipitate	Net ionic precipitation with limiting ion
Acetic acid + sodium acetate	Buffer pH behavior	Henderson-Hasselbalch classroom approximation
Acetic acid + carbonate	CO2 bubbles, acetate remains dissolved	Weak acid carbonate gas-evolution rule
BaCl2 + Na2SO4	White BaSO4 precipitate	Sulfate solubility exception with mole balance
CuSO4 + NaOH	Blue copper hydroxide precipitate	Hydroxide precipitation rule and precipitate mass estimate
FeCl3 + NaOH	Rust-brown iron(III) hydroxide precipitate	Hydroxide precipitation rule and limiting ion
NH4Cl + NaOH	Basic ammonia cue with safety note	Weak acid/base proton transfer with qualitative volatility cue
Sulfite + acid	SO2 gas-evidence card and safety note	Curated gas-evolution stoichiometry
KMnO4 + FeCl2 + acid	Purple redox solution fades toward iron(III) color	Curated balanced acidic permanganate redox equation

Reference

Direct bundled values such as molar masses, example Ksp values, Ka/Kb values, and common ion colors where available.

Estimated

Thermal changes, activity corrections, weak acid/base pH, and speciation fractions simplified for classroom-level interpretation.

Classroom model

Rule families that are useful for learning and designed for instructional use. Atomency labels these so students can reason from assumptions instead of mistaking a classroom model for professional lab analysis.