Finals Chapter 1-4 Flashcards
5 layers of earths atmosphere
troposphere, stratosphere, mesosphere, thermosphere, exosphere
What is a chemical?
Any substance that has a definite composition
CFC’s
chlorofluorocarbons
chemistry
the study of matter and the changes it undergoes
matter
anything that has mass and takes up space
mass
measurement that reflects the amount of matter
weight
measurement of the amount of matter and effect of earths gravitational pull on that matter
scientific method
systematic approach used in scientific study
qualitative data
information that relates to the five senses
quantitative data
numerical information
hypothesis
tentative explanation for what has been observed
experiment
set of controlled observations that test the hypothesis
independent variable
the variable that you plan to change
dependent variable
changes in response to the independent variable
control
standard for comparison
model
visual or verbal explanation of experimental data
theory
explanation that has been supported by many many experiments
scientific law
relationship in nature that is supported by many experiments
pure research
seeks to gain knowledge for the sake of knowledge itself
applied reserach
research undertaken to solve a specific problem
technology
practical use of scientific information
base unit
defined unit in a system of measurement based on an object or event in the physical world
second
SI unit for time
meter
SI base unit for lengh
kilogram
SI base unit for mass
derived unit
unit that is defined by a combination of base units
liter
metric unit for volume
density
ratio that compares the mass of object to its volume
kelvin
SI base unit for temperature
scientific notation
a number between and 1-10, ten raised to a power
conversion factor
ratio of equivalent. always =1
accuracy
how close a measured value is to an accepted value
precision
how close a series of measurements are to one another
percent error
the ratio of an error to an accepted value
percent error= error/accepted value x 100
graph
visual display of data
giga
10^9
mega
10^6
kilo
10^3
deci
10^-1
centi
10^-2
1/100
milli
10^-3
1/1000
micro
10^-6
nano
10^-9
pico
10^-12
substance
matter that a uniform and unchanging composition
physical property
characteristic that can be observed or measured without changing the samples composition
extensive properties
dependant of the amount of substance present (ex. mass)
intensive properties
independent of the amount of substance (ex. density)
chemical property
the ability of a substance to combine with or change into one or more other substances
states of matter
all mater that exists on earth can be classified as one of these physical forms called states of matter
solid
form of matter with its own definite shape and volume
liquid
form of matter that flows, has a constant volume, and takes the shape of its container
gas
form of matte that flows to conform to the shape of its container and fills the entire volume of its container
vapor
gaseous state of a substance that is liquid or solid at room temperature
physical change
changes that alter a substance with out changing its composition
chemical change
process that involves one or more substances changing into new substances
law of conservation of mass
mass is neither created nor destroyed during a chemical reaction
mixture
combination of two or more substances
heterogeneous
can see the difference
homogeneous
cant see the diffrence. solution
filtration
technique that uses a porous barrier to separate solid from liquid
distillation
separation using boiling points
element
pure substance that can not be separated into simpler substances
Compound
Combination of two or more different elements combined chemically
Law of definite proportions
Regardless the amount, a compound is always composed of the same elements in the same proportion by mass
Percent by mass
Ratio of the mass of each element to the total mass of the compound
Law of multiple proportions
When different compounds are formed by a combination of the same elements, different masses of one element combine with the same relative mass of the other element in a ratio of small whole numbers
Dalton’s atomic theory
All matter is composed of small particles called atoms
Atom
Smallest particle of an elements that retains the properties of the element
Cathode ray
Ray of radiation originated from the cathode end of the tube
Electrons
Negatively charged particles that are part of all forms of matter
Nucleus
Tiny dense region in the center of an atom that contained all of an atoms positive charge and virtually all it’s mass
Proton
A subatomic particle carrying a positive charge
Neutron
Subatomic particle carrying no charge
Atomic number
Number of protons in an atom
Isotope
Atom with same number of protons but different number of neutrons
Mass number
Sum of protons and neutrons in the nucleus
Atomic mass number
Defined as 1/12 the mass of a carbon -12 atom
Atomic mass
Weighed average mass of the isotopes of that element
Nuclear reactions
Reactions that involve a charge in an atoms nucleus
Radioactivity
Spontaneously emitted radiation
Radiation
Rays and particles emitted by radioactive material
Radioactive decay
Unstable nuclei lose energy by emitting radiation
Alpha radiation
Radiation deflected toward the negatively charged plate
Alpha particles
2+ charge
Nuclear equation
Shows the atomic number and mass number of particles involved
Beta radiation
Radiation deflected towards positively charge plate
Beta particles
1- charge
Gamma rays
High energy radiation that possess no charge
