Chapter 4 & 5

2. Atoms of the same element that have different numbers of neutrons.
3. The number of waves that pass a certain point every second.
4. The total number of protons and neutrons. (2 words)
8. Atomic _______ spectrum is the set of frequencies of EMR emitted by atoms of an element.
10. The 4 types of orbitals (sublevels) from lowest energy to highest.
11. The smallest particle of an element that still shows the characteristics of that element. proton A unit of positive electrical charge and what defines the element.
13. The distance between identical points on a wave.
15. Electron ____ structures are a graphical way to represent valence electrons.
16. The center of the atom containing the protons and the neutrons.
19. Electron ______ is the arrangement of electrons in an atom.
21. A unit with no electrical charge.
22. ___________ radiation is energy that travels in waves.
27. The mnemonic for the sequence of colors in visible light.
28. Higher frequencies (shorter wavelengths) have ______ energy.
29. The first scientist to develop and accepted theory on atoms.

1. The average mass of all an element’s isotopes. (2 words)
5. State when an atom gains energy.
6. The minimum amount of energy that can be gained or lost by an atom.
7. The first person to propose the idea of atoms.
9. The lowest allowable energy state of an atom.
10. There are this many forms of radiation.
11. The number of protons in an element (2 words)
12. Particles of EMR with no mass that carries a quantum of energy.
14. ½ the distance between a wave’s crest and trough.
17. A unit of negative electrical charge.
18. Electrons in the outermost orbitals.
20. An atom that has either a positive or a negative charge
23. All waves travel at the speed of _____.
24. The atomic _____ is a 3-dimensional region surrounding the nucleus where electrons are found.
25. This scientist developed a cathode ray tube led to the discovery of electrons.
26. There are 7 principal orbital _______.