chempirical
For teachers

Chemistry tools for the classroom, free and without accounts

Pupils open a link and start: nothing to install, no sign-up, no ads, on Chromebooks, iPads and school computers alike. You get structure drawing for worksheets and exams, hazard data for practicals and an inventory for the prep room.

Open CovalentChemical inventory

Worksheets, exams and slides

Worksheets and examsStart from the worksheet or exam template, draw the structures, add answer lines and download a PDF or paste the page into Google Docs or Word. Structures from SMILESPaste a SMILES string and get a clean skeletal formula for a slide, as SVG or PNG, with formula and molar mass. Named reactionsNamed reactions with their conditions and checked Organic Syntheses procedures for the upper years.

Practicals, prepared safely

Hazards for every reagentGHS pictograms, H statements, melting and boiling points and density for over 48,000 compounds, by name, CAS number or formula. Reagent table for a practicalPaste the chemicals of an experiment and get one table with molar masses, physical data and hazards for the risk assessment. Stock solutionsWhat to weigh for 250 mL of 0.1 M sodium chloride, how far to dilute a stock, and how to make 1 M HCl from 37 % acid.

Let pupils check their own work

Each calculator shows the values it used, so a pupil can follow the working instead of copying a number.

Balancing equationsAny equation, with ions and redox half-reactions, balanced with exact whole-number coefficients. Molar massMolar mass and elemental composition for any formula, with the isotope pattern for the older years. StoichiometryThe limiting reagent, the theoretical yield and what is left over, from the amounts the pupils used. pH and bufferspH of strong and weak acids, bases and buffers from exact equilibria, including polyprotic acids. Periodic tableAll 118 elements with masses, electron configurations and electronegativity.

The prep room in order

Chemical inventoryEvery chemical with hazards, storage class, location and expiry, warnings when stock runs low or expires, and a register to print. Schools in GermanyThe Gefahrstoffverzeichnis the RiSU asks of every school, explained in German.

Questions teachers ask

Do pupils need an account?

No. Every tool works without one. Signing in only matters for the chemical inventory, so that the list follows you to other devices.

Does it run on school devices?

Yes, in any current browser: Chromebooks, iPads, Windows and macOS. Nothing is installed, so nobody needs an administrator.

What does it cost?

Nothing. The tools are free in class, for homework and for preparing lessons, without ads or trackers from other companies.

Where do the hazard data come from?

From the harmonised EU classification (CLP Annex VI) where there is one, otherwise from the aggregated notifications to ECHA, via PubChem. Where there is no classification the page says so instead of guessing; your supplier's safety data sheet stays the reference.

Something is missing or wrong?

Write to support@chempirical.com. Requests from classrooms decide what gets built next.