how close or reproducable a series of experimental measurements are to each other
accuracy
how close any measurement is to the actual measurement
systematic error
error which is consistently different than the actual value resulting from either a faulty measuring device or consistantly making the incorrect recording due to an operating error
random error
error that occurs always and can be either higher or lower than the actual value and whose magnitude is the result of operator skill and instrument precision
+/- sig fig rule
round off yoru answer to the same decimal place as the least precise piece of data used in the calculation
x/division sig fig rule
use the same number of sig digits as the least pecise piece of data involved in the calculation
scientific notation
a system to represent numbers both large and small unambiguously regarding sig figs
isoelectronic
when two different elements have the same electron configuration