Laboratory
Free PNG images in the category “Laboratory”: 2 files with transparent background, no sign-up.
The skeletal formula of isatin, a benzene ring fused to a five-membered ring with an NH and two carbonyl groups, and a scanned school worksheet titled Laboratory Activity: Pulleys, with a diagram of a spring scale and weights.
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Laboratory among the science pages
Chemistry covers the subject, experiment a single test, and microscope and test tube their own instruments. Laboratory is the place and its routine: benches, glassware, lab coats, safety rules and procedures.
The pulley worksheet
A real printed handout with problem, materials and numbered steps. Useful as an example of lab report layout, for a physics lesson on simple machines or for a teacher’s blog.
The isatin formula
Clean black lines on transparency, ready to drop into slides. It suits an organic chemistry handout, a dye-history article or a reagent label mock-up.