Question | Answer |
law of conservation of mass | the law that states that mass cannot be created or destroyed in ordinary chemical and physical changes |
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atom | the smallest unit of an element that maintains the chemical properties of that element |
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nuclear forces | the interaction that binds protons and neutrons |
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atomic number | the number of protons in the nucleus of an atom |
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average atomic mass | the weighted average of the mass of all naturally occurring isotopes of an element |
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mass number | the sum of the numbers of protons and neutrons in the nucleus of an atom |
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electromagnetic spectrum | all of the frequencies or wavelenghts of electromagnetic radiation |
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excited state | a state in which an atom has more energy than it does at its ground state |
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frequency | the number of cycles or vibrations per unit of time; also the number of waves produced in a given second of time |
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ground state | the lowest energy state of a quantizied system |
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wavelength | the distance from any point on a wave to an identical point on the next wave |
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Heisenberg Uncertainty Principle | the principle that states that determining both the position and velocity of an electron or any other particle simultaneously is impossible |
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orbital | a region in an atom where there is high probability of finding electrons |
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quantum numbers | a number that specifies the properties of electrons |
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quantum theory | the study of the structure and behavior of the atom and of subatomic particles from the view that all energy comes in tiny indivisible bundles |
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Aufbau principle | the principle that states that the structure of each successive element is obtained by adding one proton to the nucleus of the atom and one electron to the lowest-energy orbital that is available |
| element is obtained by adding one proton to the nucleus of the atom and one electron to the lowest-energy orbital that is available. |
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electron configuration | the arrangement of electrons in an atom |
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Hund's rule | the rule that states that for an atom in the ground state the number of unpaired electorns is the maximum possible and those unpaired electrons have the same spin |
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noble gases | an outer main energy level fully occupied by eight electrons |