Protons, neutrons and electrons: fill in atom tables from the atomic and mass numbers and draw Bohr models. There are 4 sheets here: protons, neutrons, electrons, bohr models, parts of an atom and vocabulary match. Pick one from the tray, print it, and add its answer key as a second page if you want one.
For a neutral atom: protons = electrons = atomic number. Neutrons = mass number − atomic number.
| Element | Symbol | Atomic number | Mass number | Protons | Neutrons | Electrons |
|---|---|---|---|---|---|---|
| Argon | 18 | 22 | 18 | |||
| Neon | 20 | 10 | 10 | |||
| Boron | B | 11 | 5 | |||
| Chlorine | Cl | 35 | 18 | |||
| Manganese | 55 | 25 | 25 | |||
| Chromium | 24 | 24 | 28 | |||
| Sulfur | S | 16 | 32 | |||
| Oxygen | 8 | 8 | 8 | |||
| Carbon | C | 12 | 6 | |||
| Beryllium | 9 | 4 | 4 |
They suit grades 6 to 10. Each sheet in the tray practices it a different way, so you can pick the one that fits.
Yes. Tick “add the answer key as page 2” before printing, or turn on Answer key to check work on screen.
Yes. Press New problems for a fresh set of the same kind, then print again. The answer key changes with it.
No. The sheets print straight from this page, free, with no sign-up.