unit one definitions Flashcards
chemistry
field of science that examines the properties and behavior of matter, as well as the change of matter
what is the scientific method
the path that leads from experiments, hypotheses, and observations into theories or laws
what is the pathway of the scientific method?
questions/observations -> hypothesis -> experimental tests -> repeatable results that either support or refute the hypothesis
observation
something you notice in nature or an experiment
hypothesis
a tentative explanation or prediction based on observations. MUST be falsifiable to be considered scientific
experiment
carried out to test a hypothesis
Theory (model)
a set of assumptions put forth to EXPLAIN some aspect of observed behavior.
why/how
law
concise statement or summary of generally observed behavior that is always the same under the same conditions.
describing WHAT will occur
law vs theory
a law is a summary of what happens.
a theory is an attempt to explain WHY it happens
matter
anything that has mass and takes up space
solid
rigid, fixed volume and shape, slightly compressible.
solid particles have some energy which causes them to vibrate back-and-forth however, they rarely move past neighboring particles
liquid
definite volume, no definite shape (assumes shape of container), slightly compressible.
particles are arranged randomly and can FLOW past each other
gas
no fix volume or shape (assumes volume and shape of container), highly compressible
particles fly around, colliding with one another and the walls of the container
gas
no fix volume or shape (assumes volume and shape of container), highly compressible
particles fly around, colliding with one another and the walls of the container
Qualitative examples
color, smell, appearance, etc.
quantitative examples
volume, speed, time, mass
pure substance
a substance with a constant composition (ex. water, sugar, etc)
can further be broken down into compounds and elements
compound
two or more DIFFERENT atoms joined together by chemical bonds in fixed ratios
(ex H2O, CaCO3, LiCl, etc)
Elements
substance that cannot be further broken down into anything simpler, composed of a single type of atom
(ex. He, Ni, Mg, etc.)