Once collected, data must be presented in a form that can reveal any patterns and relationships and that allows results to be communicated to others. Because raw data as such have little meaning, a major practice of scientists is to organize and interpret data through tabulating, graphing, or statistical analysis. Such analysis can bring out the meaning of data—and their relevance—so that they may be used as evidence.
Engineers, too, make decisions based on evidence that a given design will work; they rarely rely on trial and error. Engineers often analyze a design by creating a model or prototype and collecting extensive data on how it performs, including under extreme conditions. Analysis of this kind of data not only informs design decisions and enables the prediction or assessment of performance but also helps define or clarify problems, determine economic feasibility, evaluate alternatives, and investigate failures. (NRC Framework, 2012, p. 61-62)
Generating a Hypothesis and Developing a Model
Modeling can begin in the earliest grades, with students’ models progressing from concrete “pictures” and/or physical scale models (e.g., a toy car) to more abstract representations of relevant relationships in later grades, such as a diagram representing forces on a particular object in a system. (NRC Framework, 2012, p. 58)
anion - a negatively charged ion.
atomic number - the number of protons in the nucleus of an atom.
atomic radius - the distance from the atom's nucleus to the outermost energy level.
average atomic mass - a weighted average of all of the isotopes of that element in the universe.
cation - a positively charged ion.
effective nuclear charge (Zsubeff) - the net positive charge experienced by the valence electrons from the nucleus.
electron - a tiny particle with a negative charge that is found outside the nucleus of an atom.
electron configuration - the order in which electrons are arranged in an atom.
electronegativity - the ability of an atom to attract additional electrons.
energy sublevel - a smaller part within a primary energy level.
excited state - an atom, ion or molecule with an electron in a higher than normal energy level than its ground state.
ground state - the lowest energy state within electron orbitals.
Hund's Rule - When placing electrons in equal energy orbitals, electrons should not be paired until each equal energy orbital contains one electron.
ion - an atom with a positive or negative charge.
ionization energy - the amount of energy required to remove one valence electron from an atom.
isotope - the same element with different numbers of neutrons.
model - a physical, conceptual, or mathematical representation of a real phenomenon whose purpose is to explain and predict the observed phenomenon.
orbital - a region of space around the nucleus of an atom where an electron is likely to be found.
Pauli exclusion principle - when an orbital holds two electrons, the electrons much have opposite spin.
quantum - a specific amount of energy that can be absorbed by an electron as it moves from ground state to excited state, or released by an electron as it falls from the excited state back to ground state.
subatomic- any smaller part of an atom such as a proton, neutron, or electron.
valence electrons - electrons on the outer-most energy level of any atom.
valence shell - the outer-most energy level of an electron.
Georgia Standards of Excellence
Obtain, evaluate, and communicate information about the use of the modern atomic theory and periodic law to explain the characteristics of atoms and elements.
Evaluate the merits and limitations of different models of the atom in relation to relative size, charge, and position of protons, neutrons, and electrons in the atom.
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