Chapter 1-2 Flashcards
What does chemistry study
the composition structure and properties of matter and the changes matter undergoes
What is foundational to all the other areas of chemistry
Physical Chemistry
A hypothesis must be
repeatable and testable
What is the language of science
mathematics
What is the difference between precision and accuracy
Precision- Consistency and repeatability
Accuracy- Closeness to Actual Value
What numbers are usually certain?
Numbers obtained by counting and defined numbers
What errors reduce precision
random errors
What errors reduce accuracy
systematic errors
What are numbers without uncertainty called
exact numbers
There is always some ( blank ) in a measurement
uncertainty
What is a collection of compatible related units that can be used to measure various quantities called
system of measurement
What is the Modification of the metric system with meticulously defined standards for all units
The SI
International System of Units
What does the SI system attach to the base unit’s name its value
Prefixes
nano
Give the abbreviation
Meaning
Power of ten
n
one billionth
10(-9)
micro
Mew ( Greek u with a tale on the left)
one millionth
10(-6)
milli
m
one thousandth
10(-3)
centi
c
one hundredth
10(-2)
kilo
k
one thousand
10(3)
mega
M
one million
10(6)
What is the standard SI unit of length
Meter
what is a very important measure derived from length
volume
What is a common metric unit of volume
Liter
What is the quantity of matter in an object
Mass
what is the force of gravity upon an object
weight
what is the measurement of mass that is defined by the SI
Kilogram
What is the density represented by in the Greek alphabet
rho ( basically a “p”)
How do you find the density of an object
p= mass/ volume
Temperature is most often measured and what scale
Celsius scale
How do you convert degrees Celsius to Fahrenheit
T_f= 9/5T_c+32
how do you convert degrees Fahrenheit to Celsius
T_c = 5/9(T_f-32)
What is the coldest possible temperature
Absolute zero
how do you convert degrees Celsius into kelvin
T_c = T_k- 273.15
what is the basic unit of time in the SI
second
Name the SI standard measurement and it’s abbreviation Length Mass Volume Time Temperature Absolute Temperature Pressure Amount of Substance Energy
meter m kilogram kg liter L second s degree Celsius •C kelvin K pascal Pa mole mol joule J
Every number can be expressed as a number between one and 10 multiplied by a power of 10
True
When adding or subtracting numbers that are written in scientific notation the numbers must all be written so they have the same power of 10
(9.9 • 10^2) +(6.2 • 10^4)
(.099•10^4) etc….
To multiply- in scientific notation
add the exponents
To divide in scientific notation
subtract the exponents
What is defined as Anything that occupies space and has mass
matter
what is the energy of motion of particles
kinetic energy
What is the indirect measurement of the particles average kinetic energy
Temperature
What is the point in which kinetic energy helps to break loose particles from the rigid positions
Melting point
What is a form of matter with unique properties that make it different from everything else
substance
What are the smallest particles
Atoms
What are composed of only a single type of atom
Elements
what are groups of two or more atoms that are linked together by chemical bonds to form distinct units
Molecules
What are the abbreviations for the elements called
Atomic symbols
what are the elements that are always with two atoms
Diatomic elements
What is the most abundant element
Hydrogen
what has properties quite different from those of the elements from which it is formed
compound
what has a definite composition, that is, the relative amounts of each element in a given compound are unchangeable no matter where the compound may be found
Pure substance
pure substance are also (blank) that is, they are composed of the same kind of matter throughout a sample
homogenous
What is combined physically but not chemically
Mixture
what consists of pure substances that are incompletely mixed
Heterogeneous mixture
in a heterogeneous mixture there are distinct ( blank)
phases
What does atom mean. In Greek
Indivisible or uncut
Who proposed an atom theory and what was it called
Dalton’s atomic theory
What are two scientific laws that come from Dalton’s theory
The law of definite composition which states the ratios of the masses of each element and a given compound are always the same
The law of multiple proportions
what are used to describe a substance’s Physical appearance
Physical properties
homogenous mixtures can also be called what
Solutions
What can be used when separating homogenous mixture’s components when the components have widely different boiling points
distillation
What are the two types of distillation
Simple and fractional
what basically forms crystals by heating up a mixture
Fractional crystallization
Complex mixtures can be separated by the technique of blank. What is one of the most simple forms of this technique
Chromatography
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