Ch 1&2 Vocabulary 9/4/14 Flashcards
how closely several measurements of the some quantity made in the same way agree with one another
precision
found in the bark of the willow tree, this substance is used to reduce fever and relieve pain
salicin/aspirin
used by professional divers for breathing to avoid nitrogen narcosis
helium
pure substances that are distributed uniformly throughout a mixture
homogeneous
these are pure substances that are not elements
compounds
a physical property we can use to identify a substance
density
pure substance that contain only one kind of atom
elements
anything that has mass and takes up space
matter
this type of mixture contains substances that are not evenly mixed
heterogeneous
can only be identified by trying to cause a chemical change
chemical property
how close a measurment is to true value is the ______ of a measurment
accuracy
“all digits known with certainty as well as one estimated or uncertain digit”
significant figures
used to help scientists when taking measurements of and performing calculations with very large and very small numbers
scientific notation
the amount of matter in an object
mass
a property that can be determined without changing the nature of the substance
physical property
