complete range of wavelengths which light can have. These include infrared, ultraviolet and all other types of radiation as well as visible light
Back
energy
Front
ability to do work
Back
combustion
Front
when substances combine with oxygen and release energy
Back
entropy
Front
measure of the disorder of a system
Back
dipole-dipole forces
Front
intermolecular forces that exist between polar molecules. Active only when the molecules are close together. The strengths of intermolecular attractions increase when polarity increases
Back
equilibrium expression
Front
the expression giving the ratio between the products and reactants. It is equal to the concentration of each product raised to its coefficient in a balanced chemical equation and multiplied together, divided by the concentration of the product of reactants to the power of their coefficients
Back
compound
Front
two or more atoms joined together chemically, with covalent or ionic bonds
Back
concentration
Front
the amount of a substance in a specified space
Back
equilibrium
Front
when the reactants and products are in a constant ratio. The forward reaction and the reverse reactions occur at the same rate when a system is in this state
Back
atom
Front
the smallest object that retains properties of an element. Composed of electrons and a nucleus (containing protons and neutrons)
Back
buffer solutions
Front
solutions that resist change in their pH, even when small amounts of acid or base are added
Back
decay
Front
change of an element into a different element, usually with some other particle(s) of energy emitted
Back
chemical changes
Front
processes or events that have altered the fundamental structure of something
Back
atomic number
Front
number of protons in an element
Back
electrong
Front
one of the parts of an atom having a negative charge. Indivisible particle with a charge of -1
Back
Avogadro's number
Front
number representing the number of molecules in (1) mole: 6.022 * 10 to the 23 power
Back
basic
Front
having the characteristics of a base
Back
electrochemical cell
Front
gives an electric current with a steady voltage as a result of an electron transfer reaction
Back
anode
Front
the electrode where electrons are lost (oxidized) in redox reactions
Back
anion
Front
ions with a negative charge
Back
equivalence point
Front
occurs when the moles of acid equal the moles of base in a solution
Back
empirical formula
Front
formula showing the simplest ratio of elements in a compound
Back
cathode
Front
electrode where electrons have gained (reduction) in redox reactions
Back
enthalpy
Front
change in heat at constant pressure
Back
double bond
Front
when an atom is bonded to another atom by two sets of electron pairs
Back
central atom
Front
in a Lewis structure, usually the atom that is the least electronegative
Back
colligative properties
Front
properties of a solution that depend only on the number of particles dissolved in it, not the properties of the particles themselves. The main ones are boiling point elevation and freezing point depression.
Back
effusion
Front
movement of gas molecules through a small opening
Back
acidic
Front
describes a solution with a high concentration of H+ ions
Back
equilibrium constant
Front
value that expresses how far the reaction proceeds before reaching equilibrium. A small number means that equilibrium is towards the reactants side while a large number means that the equilibrium is towards the product side
Back
endothermic
Front
process that absorbs heat from its surroundings as the reaction proceeds
Back
dispersion forces (London dispersion forces)
Front
dispersion is an intermolecular attraction force that exists between all molecules. These forces are the result of the movement of electrons which cause slight polar moments. Generally very weak, when their molecular mass increases, so does their strength
Back
base
Front
substance which gives off hydroxide ions (OH-) in solution
Back
covalent bonds
Front
when two atoms share at least one pair of electrons
Back
electrostatic forces
Front
forces between charged objects
Back
acid
Front
compound that gives off H+ ions in solution
Back
electrodes
Front
device that moves electrons into or out of a solution by conduction
Back
Bohr's atom
Front
He made significant contributions to the atom. He understood the line spectra--the reason why only certain wavelengths are emitted when atoms jump down levels
Back
conjugate base
Front
a substance which can gain H+ ion to form an acid
Back
density
Front
mass per unit volume of a substance
Back
charge
Front
describes an object's ability to repel or attract other objects. Protons have a positive ...while electrons have a negative... Like ...repel each other, while opposites attract.
Back
cations
Front
ion with positive charge
Back
dissociation
Front
breaking down of a compound into its components to form ions from an ionic substance
Back
chemical equation
Front
an expression of a fundamental change in the chemical substance
Back
electronegativity
Front
measure of a substance's ability to attract electrons
Back
catalyst
Front
substances that speed up a chemical process without actually changing the products of reactions
Back
electrolysis
Front
changing the chemical structure of a compound using electrical energy
Back
Section 2
(50 cards)
mass number
Front
the number of protons and neutrons in an atom
Back
intramolecular forces
Front
forces within molecules. Forces caused by the attraction and repulsion of charged particles
Back
Gibb's free energy
Front
the energy of a system that is available to do work at a constant temperature and pressure
Back
neutron
Front
a particle found in the nucleus of an atom. It is almost identical in mass to a proton, but carries no electrical charge
Back
Le Chatlier's Principle
Front
states that a system at equilibrium will oppose any change in the equilibrium conditions
Back
parent isotopes
Front
an element that undergoes nuclear decay
Back
molality
Front
the number of moles of solute (the material dissolved) per kilogram of solvent (what the solute is dissolved in)
Back
Kelvin
Front
The SI unit of temperature. It is temperature in degrees Celsius plus 273.15
Back
partial pressure
Front
the pressure exerted by a certain gas in a mixture
Back
nucleus
Front
the central part of an atom that contains the protons and neutrons. Plural=nuclei
Back
molecular formula
Front
shows the number of atoms of each element present in a molecule
Back
Planck
Front
What is h?
Back
ion
Front
removing or adding electrons to an atom creates an ... (a charged object very similar to an attom)
Back
molar
Front
a term expressing molarity, the number of moles of solute per liters of solution
Back
hydrogen bonding
Front
strong type of intermolecular dipole-dipole attraction. Occurs between hydrogen and F, O or N
Back
half life
Front
the amount of time it takes for half an initial amount to disintegrate
Back
Planck
Front
He contributed to the understanding of the
Back
molecular mass
Front
the combined mass (as given on the periodic table) of all the elements in a compound
Back
limiting reagent
Front
the reactant that will be exhausted first
Back
physical property
Front
a property that can be measured without changing the chemical composition of a substance
Back
percent composition
Front
expresses the mass ratio between different elements in a compound
Back
particle
Front
small portion of matter
Back
isotopes
Front
elements with the same number of protons but have different numbers of neutrons, and thus different masses
Back
Geiger counter
Front
instrument that measures radiation output
Back
orbitals
Front
an energy state in the atomic model which describes where an element will likely be
Back
neutral
Front
an object that does not have a positive or negative charge
Back
molecular geometry (VSEPR)
Front
shape of a molecule, based on the relative position of the atoms
Back
intermolecular forces
Front
forces between molecules
Back
mole fraction
Front
the number of moles of a particular substance expressed as a fraction of the total number of moles
Back
Heisenberg uncertainty principle
Front
the principle states that it is not possible to know a particle's location and momentum precisely at any time
Back
nm
Front
abbreviation for nanometers. A nanometer is equal to 10 to the -9 power meters
Back
frequency
Front
number of events in a given unit of time. When describing a moving wave, means the number of peaks which would pass a stationary point in a given amount of time
Back
mole
Front
a collection of 6.022 * 10 to the 23 power number of objects. Usually used to mean molecules
Back
ideal gas law
Front
Back
periodic table
Front
grouping of the known elements by their number of protons. There are many other trends such as size of elements and electronegativity that are easily expressed in terms of the periodic table
Back
kinetic energy
Front
energy an object has because of its mass and velocity. Objects that are not moving do not have this.
Back
hydrolysis
Front
the reactions of cations with water to produce a weak base or of anions to produce a weak acid
Back
mixture
Front
composed of two or more substances, but each keeps its original properties
Back
octet
Front
In Lewis structures, the goal is to make almost all atoms have this structure. This means they will have access to (8) electrons regularly, even if they do have to share some of them
Back
Lewis structures
Front
a way of representing molecular structures based on valence electrons
Back
oxidation number
Front
a number assigned to each atom to help keep track of the electrons during a redox-reaction
Back
pH
Front
measures the acidity of a solution. It is the negative log of the concentration of the hydrogen ions in a substance
Back
photon
Front
massless packet of energy, which behaves like both a wave and a particle
Back
molarity
Front
the number of moles of solute (the material dissolved) per liter of solution. used to express the concentration of a solution
Back
ionic bond
Front
when two oppositely charged atoms share at least one pair of electrons but the electrons spend more time near one of the atoms than the other
Back
Graham's law
Front
the rate of diffusion of a gas is inversely proportional to the square root of its molar mass
Back
ionization energy
Front
energy required to remove an electron from a specific atom
Back
oxidation-reduction-reaction
Front
a reactions involving the transfer of electrons
Back
exothermic
Front
process that gives off heat to the environment
Back
molecule
Front
two or more atoms chemically combined
Back
Section 3
(40 cards)
quantum
Front
Something that comes in discrete units
Back
wave
Front
A signal which propagates through space
Back
radiation
Front
Energy in the form of photons
Back
reduction reaction
Front
A reaction in which a substance gains at least one electron
Back
reactants
Front
Substances initially present in a chemical reaction
Back
radiant energy
Front
Energy which is transmitted away from its source, for example, energy that is emitted when electrons transition down one level to another
Back
single bond
Front
When an electron pair is shared by two atoms
Back
pressure
Front
Force per unit area
Back
spontaneous reaction
Front
A reaction that will proceed without any outside energy
Back
weak bases
Front
Substances capable of accepting hydrogen but do not completely ionize in solution
Back
wavelength
Front
On a periodic curve, the length between two consecutive troughs (low points) or peaks (high points)
Back
proportion
Front
An equality between two ratios
Back
subshell (suborbital)
Front
One part of a level, each of which can hold different numbers of electrons
Back
stoichiometry
Front
The study of the relationships between amounts of products and reactants
Back
polar molecules
Front
Molecule with a partial charge
Back
radioactive
Front
Substance containing an element which decays
Back
shells (orbitals)
Front
Where the electrons generally are; they are composed of four types of sub...; s, p, d and f
Back
work
Front
Expression of the movement of an object against some force
Back
pOH
Front
Measures the basicity of a solution. It is the negative log of the concentration of the hydroxide ions
Back
volume
Front
Measures the size of an object using length measurements in three dimensions
Back
proton
Front
Particle found in a nucleus with a positive charge. Number of these gives the atomic number
Back
solute
Front
The substance (solid, liquid or gas) dissolved in a solution, for example, the salt in saltwater
Back
van der Waals equations
Front
An equation for non-ideal gases that accounts for intermolecular attraction and the volumes occupied by gas molecules
Back
titration
Front
The process used to take a solution of unknown concentration with a solution of a known concentration for the purpose of finding out more about the unknown solution
Back
states of matter
Front
Solid, liquid, gas and plasma. Plasma is a "soup" of disassociated nuclei and electrons, normally found only in stellar objects
Back
valence electrons
Front
The electrons in the outermost shell of an atom
Back
specific heat
Front
The amount of heat it takes for a substance to be raised by one degree Celsius
Back
STP
Front
Standard Temperature and Pressure. 0 degrees Celsius and 1 atm
Back
quantum numbers
Front
Set of numbers used to completely describe an electron
Back
potential energy
Front
The energy an object has because of its composition or position
Back
solvent
Front
Liquid in which something is dissolved, for example the water in saltwater
Back
products
Front
The compounds that are formed when a reaction goes to completion
Back
ratio
Front
The relative size of two quantities expressed as the quotient of one divided by the other; a:b or a/b
Back
principal quantum number (n)
Front
The number related to the amount of energy an electron has and therefore describing which shell the electron is in
Back
SI Unit
Front
Standards for Systeme International d'Unites, an international system which establishes a uniform set of measurement units
Back
weak acid
Front
Substances capable of donating hydrogen but do not completely ionize in solution
Back
salts
Front
Ionic compounds that can be formed by replacing one or more of the hydrogen ions of an acid with another positive ion
Back
velocity
Front
Speed of an object; the change in position over time
Back
thermodynamics
Front
The study of temperature, pressure, volume and energy flow in chemical reactions
Back
solution
Front
Mixture of a solid and a liquid where the solid never settles out, for example, saltwater