chemistry
study of matter and the changes matter undergoes
scientific method
observation and experiment, hypothesis formation, law development, and theory adoption
qualitative
descriptive data
quantitative
numerical data
hypotheis
a working model of all the facts and is adjusted as new information is discovered
law
a verbal or mathematical summary of working relationships
theory
unifying principle that explains a large body of observations and laws
matter
anything that has mass and occupies space
pure substance
form of matter that has fixed composition and distinct properties
element
pure substance that cannot be decomposed into simpler substances by a chemical reaction
compound
pure substance that are composed of two or more elements in fixed proportion
mixture
when pure substances are combined
homogeneous mixture
a mixture uniform throughout
heterogeneous mixture
a mixture in which components are not evenly dispersed
physical properties
those that can be observed and measured without changing the identity or chemical composition of the substance
chemical properties
observation of this can only occur as a substance is converted to another species (element or compound) in a chemical reaction
extensive properties
Vary with the amount of matter being considered
intensive properties
independent of the amount of material
macroscopic properties
properties that are seen with the naked eye
microscopic properties
properties than can only been seen with assistance to the eye
international system of units
mass- kg
length- m
time- s
temp- K
amount-mol
weight
force exerted on the object by gravity
mass
measure of an object's resistance to external forces and amount of matter in the object (the same everyhere)
volume
measure of the amount of space an object occupies
density
ratio of the mass to the volume
kelvin
SI unit for temp
significant figures
digits allowed in a reported answer
accuracy
closeness of measurements to the correct or accepted value of the quantity measured
precision
closeness of a set of measurements of the same quantity made in the same way
atom
the extremely small, indivisible particles that make up elements
law of definite proportions
all purified samples of a compound contain its constituent elements in the same proportions by mass (Dalton's second postulate)
law of multiple proportions
when two elements form more than one compound, the masses of the elements in the compound are related by small whole number ratios (consequence of Dalton's second postulate)
law of conservation of mass
mass is conserved in chemical reactions because atoms are conserved since they are rearranged to form new combinations of atoms we recognize as new compounds
atomic number
number of protons
mass number
total number of neutrons and protons
isotopes
atoms of a given element that differ in the number of neutrons and consequently in mass
periodic table
...
periods
horizontal rows on the periodic table
groups
vertical columns on the periodic table and have similar chemical and physical properties
families
...
metals
...
nonmetals
...
metalloids
...
nomenclature
term that means naming compounds
binary compiunds
...
ternary compounds
...
inorganic compounds
a compound with a combination of nonmetal elements as the first element is the one farthest to the left
organic compounds
...
molecular compounds
...
acid
compounds that can dissolve reactive metals (by consuming loose electrons) and produce H+ when dissolved in water
base
compounds that neutralize acids and produce OH- when dissolved in ions
salt
compounds that form when acids are mixed with bases and water is removed
hydrates
ionic compounds that have specific numbers of water molecules attached to them, even in solid state
oxoacid
...
oxoanion
...
electron
...
nucleus
...
proton
...
neutron
...
ion
when an atom acquires a charge by gaining or losing electrons
anion
what forms when a nonmetal gains electrons forming negative ions
cation
what forms when a metal loses a electron, forming positive ions
monatomic ion
...
polyatomic ion
when a group of atoms requires a net charge
alkali metals
...
alkaline earth metals
...
halogens
...
noble gases
...
radioactivity
...
radiation
...
alpha particle
...
alpha ray
...
beta particle
...
beta ray
...
gamma ray
...
molecule
a discrete particle composed of atoms that are bonded together in fixed arrangement
allotrope
...
diatomic molecule
contain two atoms (go to 7 make a 7)
polyatomic molecule
contain more than two atoms
chemical formula
reflects the number of the different types of atoms in the substance
molecular formula
...
structural formula
depicts the spatial arrangement of the atoms in the substance
empirical formula
the formula for an ionic compound with the smallest whole number ratio
JJ thompson
he observed negative particle beams in cathode ray tubes
RA Millikan
calculated charge on electron from the rate of descent charged oil droplets in an electric field
E Rutherford
observed deflection of alpha particle by gold foil
E Rutherford
observed protons ejected from elements bombarded by alpha particles
J. Chadwick
Observed neutral particles heavy enough to eject protons from wax
JJ Thompson
discovered atoms contain electrons with a negative charge
E Rutherford
discovered a positive nucleus is surrounded by positively charged protons and negative electrons
J. Chadwick
discovered a nucleus contains neutral neutrons