Answer:
- atomic number
- electron
- element
- atom
- neutron
- nucleus
- proton
Explanation:
1. number of protons in an atom — atomic number
2. negatively charged particle circling nucleus — electron
3. matter made up of just one type of atom — element
4. building block of matter — atom
5. neutrally charged particle nucleus — neutron
6. center of the atom made up of protons and neutrons — nucleus
7. positively charged particle in the nucleus — proton
