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Atoms & Periodic T.
Chapter 17
Term | Definition |
---|---|
Atoms | The smallest particle of an element that still retains the properties of the element. |
Nucleus | Positively charged center of an atom that contains protons and neutrons and is surrounded by a cloud of electrons. |
Proton | Particle, composed of quarks, inside the nucleus of atom that has a charge of 1+. |
Neutron | Neutral particles, composed of quarks, in the nucleus of an atom. |
Electron | Particles surrounding the center of an atom that have a charge of 1-. |
Quark | Particles of matter that make up protons and neutrons. |
Electron Cloud | Area around the nucleus of an atom where the atom's electrons are most likely to be found. |
Atomic Number | Number of protons in an atom's nucleus |
Mass Number | Sum of the number of protons and neutrons in an atom's nucleus. |
Isotope | Atoms of the same element that have different numbers of neutrons. |
Average Atomic Mass | Weighted-average mass of the mixture of an element's isotope. |
Periodic Table | Organized list of all known elements that are arranged by increasing atomic number and by changes in chemical and physical properties. |
Group | Vertical column in the periodic table. |
Electron Dot Diagram | Uses the symbol for an element and dots representing the number of electrons in the element's outter energy level. |
Period | Horizontal row in the periodic table; the amount of time it takes one wavelength to pass a fixed point; is expressed in seconds. |