Atomic Mass - Choice Activity

1. A unit of mass equal to 1.66 x (-24)10 grams.
3. A row of the periodic table.
7. a substance formed from the combination of two or more metals.
12. Elements in the group containing Florine, chlorine, and bromine, among others.
14. Atoms of the same element that have different numbers of neutrons in the nucleus.
15. A fundamental property of matter that can be either positive or negative.
16. Elements that are typically shiny and good conductors of heat and electricity.
17. A particle found in the nucleus with mass similar to the proton but with zero electric charge.
18. A column of the periodic table.
19. One of the discrete allowed energies for electrons in an atom.
21. The average mass of all the known isotopes of an element, expressed in amu.

2. The number of protons in the nucleus of an atom; the atomic number determines what element the atom represents.
4. Elements in the first two groups of the periodic table.
5. The electrons in the highest, unfilled energy level of an atom.
6. A chart that organizes the elements by their chemical proporties and increasing atomic number.
8. A nucleus is stable if it stays together.
9. A nucleus is radioactive if it spontaneously breaks up, emitting particles or energy in the procces.
10. The number of protons plus the number of neutrons in the nucleus.
11. Elements that are poor conductors of heat and electricity.
13. A particle found in the nucleus with a positive charge exactly equal and opposite of the electron.
17. The tiny core at the center of an atom containing most of the atoms mass and all of its positive charge.
20. A partical with an electric charge