Why a checklist before every lab
A chemistry bench is the one place in a high-school education where a careless step can actually hurt someone. Acids burn, fumes harm lungs, and a hot plate left on near a flammable solvent does not forgive inattention. A pre-lab checklist is not bureaucracy — it is the routine that makes safe, prepared work automatic, so that on the day a reaction goes sideways the student's hands already know what to do.
It also does something quieter: it forces the student to arrive ready. The most dangerous lab partner is the one who skimmed the procedure in the hallway. This checklist closes that gap. Print one for every experiment, work top to bottom, and do not pick up a single piece of glassware until the last box is checked.
The goal is not to follow rules. It is to walk to the bench already knowing the hazards, the steps, and the result you expect.
1 — Safety
Nothing below this section happens until everything in it is done. No exceptions, every lab, every time.
- Splash-proof safety goggles on — over the eyes, not pushed up on the forehead.
- Nitrile gloves on, correct size, no holes; sleeves down and long hair tied back.
- Closed-toe shoes and a lab coat or apron; no loose clothing near the bench.
- The Safety Data Sheet (SDS) read for every chemical in use — hazards, first aid, and disposal noted.
- Fume hood located and working, or the room ventilated, for any reaction producing gas or vapor.
- Eyewash station, safety shower, fire extinguisher, and spill kit located — you know where each one is before you start.
- Waste containers identified — you know exactly where each product and leftover reagent goes.
2 — Setup
With safety confirmed, build the bench so the work flows without scrambling mid-reaction.
- The full procedure read end to end — not skimmed — so you know what step comes next.
- All glassware gathered, clean, and dry (unless the procedure calls for it wet) and laid out in order of use.
- Burette, pipette, graduated cylinder, or volumetric flask selected to match the precision the step requires.
- Balance located and calibrated/tared; you know which masses you need to record and to how many decimal places.
- Reagents located, labels double-checked against the procedure, and concentrations confirmed.
- Hot plate, Bunsen burner, or water bath set up safely — flammables cleared away from any heat or flame.
- Lab notebook open to a fresh, dated page with the title and question already written.
3 — Readiness: the pre-lab questions
This is the section that separates a technician from a chemist. Before the first measurement, the student should be able to answer these in writing — in the lab notebook, in their own words.
- What is the question? State, in one sentence, what this experiment is trying to find out or measure.
- What is the chemistry? Write the balanced equation (or the key relationship) the experiment depends on.
- What is my prediction? A specific, numerical expectation — the approximate endpoint volume, the expected color change, the sign and rough size of ΔT.
- What am I measuring, and in what units? Name every quantity you will record, its unit, and its uncertainty.
- What could go wrong? Identify the one or two steps most likely to introduce error, and how you will minimize them.
- What does success look like? Know, before you begin, what a reasonable result would be — so an absurd number raises a flag at the bench, not a week later.
A student who answers all six is not guessing their way through a recipe — they are running an experiment they understand, with a result they can already roughly predict. That is exactly the readiness the lab-notebook entry is built to capture, and the kind of preparation a lab defense is designed to reward.