LATEST VERSION
-A typical absorption spectrum has one or more peaks in absorbance
percent error - CORRECT ANSWER The percent that an estimated quantity differs from
the actual amount
-can be calculated to measure the accuracy of
a measurement. To calculate % Error simply use the following equation:
% Error = |Measured or Experimental Value - Expected or Theoretical Value| / Expected
or Theoretical Value x 100
mean - CORRECT ANSWER average
precision - CORRECT ANSWER-the closeness with which several measurements of
the same quantity agree.
-The precision of a measurement is limited by the uncertainty of the measuring device.
Uncertainty is often represented by the symbol ± ("plus or minus") followed by an
amount.
accuracy - CORRECT ANSWER-describes how 'correct' a measured or calculated
value is -how close the measured value is to the actual
value
depends on three things:
-the smallest unit on the measuring scale
-the ability of the observer to read the scale properly
-the degree of precision of the measuring instrument
and scale
variance - CORRECT ANSWER-can be used to measure the variability in a group of
measurements
-square of the standard deviation
-
standard deviation - CORRECT ANSWER-can be used to measure the variability in a
group of measurements
-calculated by taking the square root of the variance
-The lower the standard deviation of a set of measurements, the greater the precision
-often reported with the signs + in front of the number
+ or - The square root of the variance.
meniscus - CORRECT ANSWER Curve of the liquid in a cylinder (read the bottom of
the curve)