PLB REVIEW

2. How does the size of a proton compare to the size of a neutron?
4. A neutron has a
7. An atom with an unequal number of protons and electrons is said to have (a) ___.
12. Classification system for elements is called:
15. The __________ of an atom is the sum of the protons and neutrons in the nucleus of that atom.
17. The columns on the periodic table that describe the number of electrons in the atomic structure of the element:
20. A particle that moves around the nucleus is a(n)...
21. The cloud-like space that electrons travel around:
22. Where are protons and neutrons found in an atom?

1. Where are electrons found in an atom?
3. TWO or more atoms bonded (stuck) together.
5. how many subatomic particles are there
6. What is the smallest piece of a substance that is still that substance called?
8. the central region of an atom where its neutrons and protons are is its
9. The building blocks of elements
10. All elements are composed of
11. What is the study of matter?
13. The dense, positively charged mass located in the center of the atom.
14. In terms of matter, the atom is almost entirely filled with _____
16. The _________ of an element equals the number of protons in an atom of that element
18. Where are electrons of an atom found?
19. Atoms of the same element must always have the same number of _________