post lab discussion: exp. 1 Flashcards
amt. of matter in an object
mass
weighing by difference
(mass of container + object to weigh) – mass empty container
direct weighing
making use of tare button or re-zero
identify the balance used:
most weighing of amounts that are specified to only two or three significant figures
top loading balance
identify the balance used:
used whenever you desire four or
more significant figure accuracy
analytical balance
what is the accuracy of
top-loading balance -
analytical balance -
top-loading balance - +/-1mg
analytical balance - +/- 0.1mg
what is the reason to not handle objects to be weighs with bare hands
as moisture, grease and dirt on our fingers will affect the weight of the objects
to weigh accurately, all objects must be at ____
room temperature
space occupied by matter
volume
this instrument iis not design to measure volumes accurately
beaker and flask
what type of pipet is used in experiment 1
serological pipet
it is the process of configuring an instrument to provide a result for a sample within an acceptable range
calibration
This technique works for
thermometers, spring scales, and
other measuring instruments as well.
scale increments
difference between
population -
sample -
population - population
sample - subset of population
this is obtained through the process of sampling
sample
it is referred to as measures of center or central location
Measure of central tendency
also known as the arithmetic
average
mean
middle value in distribution when the values are arranged in ascending or descending order
median
it describes the reproducibility of
measurements; the closeness of results to each other.
precision
range is also called as
spread
Another term to describe the precision of a set of replicate results.
range
a statistically useful description of the scatter of the values determined in a series of runs
sample standard deviation
sample standard deviation:
* large std. dev. =
* small std. dev =
- large std. dev. = far from the mean
- small std. dev = close to the mean
it is the ratio of the standard deviation to the mean
coefficient of variation
coefficient of variation is another method of describing ____
precision
it indicates the closeness of the measurement to its true or accepted value and is expressed by the error.
accuracy
two values resulting from calculating the confidence interval.
confidence limit
it provides the best estimate of the population’s or sample’s mean
confidence interval
reporting computed data:
one of the best way of indicationg reliability is to give a confidence interval at the ___ or ___ confidence limit
90% or 95%
it tests for outliers
Q-test
