click below
click below
Normal Size Small Size show me how
chapter 17
Term | Definition |
---|---|
1. atom | which is the smallest piece of matter that still retains the property of the element. |
2. atomic number | number of protons in an atom's nucleus. |
3. average atomic mass | weighted-average mass of the mixture of an element's isotopes. |
4. eletron | particles surrounding the center of an atom that have a charge of 1-. |
5. electron cloud | area around the nucleus of an atom where the atom's electrons are most likely to be found. |
6. electron dot diagram | uses the symbol for the element and dots representing the number of electrons in the element's outer energy level. |
7. group | vertical column in the periodic table. |
8. isotope | atoms of the same element tat have different numbers of neutrons. |
9. mass number | sum of the number of protons and neutrons in an atom's nucleus. |
10. neutron | neutral particle, composed of quarks, inside the nucleus of an atom. |
11. nucleus | positively charged center of an atom that contains protons and neutrons and is surrounded by a cloud. |
12. period | horizontal row in the periodic table. |
13. periodic table | organized list of all known elements that are arranged by increasing atomic number and by changes in chemical and physical properties. |
14. proton | particle, composed of quarks, inside the nucleus of an atom that has a charge of 1+. |
15. quark | particles of matter that make up protons and neutrons. |