Developing a Model of the Atom

_________ knowledge: knowledge coming directly from observations

Definition: knowledge based on ideas created to explain observations

Definition: a mental or physical representation of a theoretical concept

Definition: a comparison of a situation, object, or event with more familiar ideas, objects, or events

Definition: a comprehensive set of ideas that explains a law or a large number of related observations

Scientific theories are dynamic;they may continually undergo refinement and change.

Who first proposed that everything is composed of "atoms", which are physically indivisible?

Who proposed that all atoms of an element have identical properties, and atoms of different elements have different properties?

Who proposed that "Atoms cannot be subdivided, created, or destroyed", but can "combine in simple whole-number ratios to form chemical compounds."?

law of conservation of ____: the law stating that during a chemical reaction matter is neither created nor destroyed

Definition: a medieval chemical philosophy or practice, the principal goals of which were to transmute elements

Definition: involving measurements related to number or quantity

Definition: a negatively charged subatomic particle

Definition: a positively charged subatomic particle in the nucleus of an atom

Definition: an uncharged subatomic particle in the nucleus of an atom