Measurement and Separation Techniques Flashcards
observations of the
physical and chemical properties
and changes that matter undergoes
that are often reported
quantitatively
Measurement
quantify the property of an object and gives full context to
the numbers of the property being measured
Units
nvented by French in the 18th century
Metric system
based on the powers of ten
Metric system
system used in some US countries
English system
1960
International system of Units (SI Units)
global
standard definition of units of measurement
International system of Units (SI Units)
remain the same regardless of the place where it is used
International system of Units (SI Units)
other units of measurement obtained by
a combination of base units
Derived units
give the SI Base Unit and symbol of
Length
Meter, m
give the SI Base Unit and symbol of
Mass
Kilogram, kg
give the SI Base Unit and symbol of
Time
Second, s
give the SI Base Unit and symbol of
Temperature
Kelvin, K
give the SI Base Unit and symbol of
Amount of Substance
Mole, mol
give the SI Base Unit and symbol of
Electric Current
Ampere, A
give the SI Base Unit and symbol of
Luminous intensity
Candela, cd
give the SI Base Unit and symbol of
Density
gram per cubic meter, g/m3
give the SI Base Unit and symbol of
Speed
Meter per second, m/s
give the SI Base Unit and symbol of
Energy
Joule, J
Formula for 1J
kg·m2/s2
Temperature conversion factors for cels9 ius
C=(F- 32) 5/9
Temperature conversion factors for fahrenheit
F=9/5(C)+32
Temperature conversion factors for fahrenheit
K= C+273
Give prefix and sym
the only digits in a given measurement that are certain and are considered practical for use in calculations
involving scientific measurements
Significant Figures
true or false
A measurement with more SF is more certain than a
measurement with fewer SF
true
true or false
A measurement with less SF is more certain than a
measurement with more SF
false
Rules in Counting Significant Figures
- All nonzero digits
are significant - All zeroes between nonzero digits (internal zeroes) are
significant. - Zeroes before the
first nonzero digits
(leading zeroes) are
not significant - Zeroes after the last nonzero digits (trailing zeroes) may or may not be
significant.
what are the two operations with significant figures
- Addition and Subtraction
- Multiplication and Division
must have the same number of decimal places as the
measurement with the fewest number of decimal places.
Addition and Subtraction
follow the least
number of significant figures from the original measurement.
Multiplication and Division
combination of
trueness and precision
Accuracy
nearness of
measurement to the true value
Trueness
nearness of the
values of multiple
measurements to each other
Precision
Physical Methods of Separation
Filtration
Distillation
Chromatography
involves the separation of the solid component of
a mixture from its liquid component
Filtration
solids mixed with
gases
Filtration
mixture passes through porous surface or
membrane that enables liquids or gases to pass but the solids
Filtration
separated solids
Residue
gas without the solid component
Filtrate
Examples of filtration
air conditioners and water purifiers
separate two or more different liquids and
gases that form a mixture
Distillation
can also be used to separate solids that are small for porous membranes to separate from their fluid medium, relies on volatilities of components
Distillation
– condensed vapor
Distillate
examples of distillation
perfume, alcoholic drinks, and, crude oil production; and
desalination of seawater
can be used to separate constituent parts of a mixture, particularly homogenous mixtures
Chromatography
fixed mediums could be
paper, gel, or cellulose
