126 terms

Chemistry EOC Review

activation energy
the minimum amount of energy required by reacting particles in order to form the activated complex and lead to a reaction
refers to how close a measured value is to an accepted value
a mixture of elements that has metallic properties
alpha particle
a particle with two protons and two neutrons, with a 2+ charge; is equivalent to a helium-4 nucleus
the smallest particle of an element that retains all the properties of that element; is electrically neutral, spherically shaped, and composed of protons, neutrons, and electrons
Arrhenius Model
states that an acid is a substance that contains hydrogen and ionizes to produce hydrogen ions, and a base is a substance that contains hydroxide grop and produces hydroxide ions
aufbau principle
states that each electron occupies the lowest energy orbital available
Avogadro's number
the number 6.02 x 10^23 which is representative of the number of particles in a mole
the height of the wave from origin to crest, or from the origin to a trough
average atomic mass
determined by multiplying each number isotope by the percent, and adding all of the products
an ion that has a negative charge; forms when valence electrons are added to the outer energy level
atomic number
the number of protons in an atom
beta particle
a high speed electron with a 1- charge that is emitted during radioactive decay
an insturment tha tis used to measure atmospheric pressure
Boyle's Law
states that volume of a given amount of gas held at a constant temp varies inversely with the pressure
Bronsted Lowry model
model of acids and bases in which an acid is a hydrogen ion donor and the base is a hydroxide ion acceptor
an ion that has a positive charge; forms when valence electrons are removed, giving the in a stable electron configuration
chemical change
the process involving one or more substances changing into new substances; also called a chemical reaction
chemical property
the ability or inability of a substance to comine with or change into one or more new substances
Charles's Law
states that volume of a given mass of gas is directly proportional to its kelvin temp at constant pressure
a substance that increases the rate of a chemical reaction by lowering the activation energy
the number written in front of a reactant or product
combined gas law
a single law combing boyles, charles, and lussacs laws that states the relationship among pressure, volume, and temp of a fixed amount of gas
combustion reaction
a chemical reaction that occurs when a substance reacts with oxygen, releasing energy in the form of heat and light; hydrocarbon + oxygen yields carbon dioxide + water
covalent bond
a chemical bond that results from the sharing of valence electrons; electronegativity difference is less than 1.7; two or more nonmetals
cathode ray
J.J. Thompson's experiment in which he discovered electrons and protons; created the plum pudding model
combination of two or more elements
Dalton's atomic theory
5 part theory; right-everything is made of atoms, atoms combine and separate, and atoms form simple whole number ratios. wrong- you can't divide and atom, and he didn't know about isotopes
Dalton's law of partial pressures
states that the total pressure of amixture of gases is equal to the sum of the pressures of all the gases in the mixtures
decomposition reaction
a chemical reaction that occurs when a single compound breaks down into two or more elemtns or new compounds
delocalized electrons
the electrons involved in metallic bonding that are free to move easily from one atom to the next throughout the metal and are not attached to any particular atom
when substance changes from gas/vapor to a solid, without first becoming liquid
double replacement reaction
a chemical reaction that involves the exchange of positive ions between two compounds and produces either a precipitate, a gas, or water
dependent variable
the variable whose value depends on the independent variable
dipole-dipole forces
the attractions b/w oppositely charged regions of polar molecules
a negatively charged, fast moving particle found in the empty space surrounding nucleus
electron configuration
the arrangement of electrons in an atom
indicates the relative ability of an elements atoms to attract electrons in a chemical bond
electron sea model
shows that all metal atoms contribute their valence electrons to form a sea of electrons
a pure substance that cannot be broken down into simpler subtances by physical or chemical means
a chemical reaction in which a grater amount of energy is required to break the existing bonds than is released when the new bonds form in the product molecules; heat absorbed
the heat content of a system at constant pressure
a measure of the randomness of the particles of the system
a chemical reaction in which more energy is released than is required to break bonds in the initial reaction; heat released
Gay-Lussac's law
states that the pressure of a given mass varies directly with the temperature when volume remains constant
gamma rays
high energy radiation that has no electrical charge and no mass, is not deflected by electric or magnetic fields, usually accompanies alpha and beta radiation, and accounts for most of the energy lost during radioactive decay
heterogenous mixture
one that does not have a uniform composition and in which the individual substances remain distinct
homogeneous mixture
one that has a uniform composition throughout and always has a single pahse; also called a solution
Hund's rule
states that single electrons with the same spin must occupy each equal energy orbital before additional electrons with opposite spins can occupy the same orbital
hydrogen bond
a strong dipole dipole attraction bw molecules that contain a hydrogen atom bonded to a small, highly electronegative atom with at least one lone electron pair; usually N, O, F
a compound that has a specific number of water molecules bound to its atoms
ideal gas law
PV=nRT; temp in kelvin, R depends on P units
independent variable
variable that the experimenter plans to change
atoms of the same element with the same number of protons, but different number of neutrons
ionic bond
metal with a nonmetal; hard, rigid, brittle solids, high melting and boiling points, conducts electricity in the aqueous and molten states
describes a substance that cannot be dissolved in a given solvent
describes two liquids that can be mixed together but separate shortly after you cease mixing them
ionization energy
the energy required to remove an electrn from a gaseous atom; generally increases left to right, and decreases tope to bottom. (florine=greatest)
the SI unit of heat and enegy
kinetic molecular theory
explains the properties of gases in terms of the energy, size, and motion of thier particles
law of conservation of energy
states that in any chemical or physical process, energy may change from one form to another, but it is neither created, nor destroyed
law of conservation of mass
in any physical change or chemical reaction, mass is conserved; mass can be neither created nor destroyed
law of conservation of charge
states that charge can be transferred from one object to another but cannot be created or destroyed
Lewis Dot structure
a model that uses electron dot structures to show how electrons are arranged in molecules; lines represent bonding pairs
limiting reactant
reactant that is totally consumed during a chemical reaction, limits the exten of the reaction and dtermines the amount of product
anything that has mass and takes up space
a physical blend of two or more pure substances in any proportion in which each
forms when two or more atoms covalently bond and is lower in potential energy than its constituent atoms
mass number
the number after the elements name, representing the sum of its protons and neutrons
left side of periodic table; good conductor of heat and electricity, ductile, malleable, generall shiny
an element that has properties of both metals and nonmetals; found along the steps lines on periodic table
describes two liquids that are soluable in each other
metallic bond
the attraction of a metallic cation for delocalized electrons
molecular formula
a formula that specifies the actual number of atoms of each element in one molecule or formula unit of the substance; done after empirical formula
empirical formula
percent to mass, mass to mole, divide by small, multiply till whole
heat of fusion
the amount of heat required to melt one mole of a solid substance; 334j/g; Q=mHf
heat of vaporization
the amount of heat required to evaporate one mole of a liquid; 2260j/g; Q=mHv
the number of moles of solute dissolved per liter of solution; moles of solute/liters of solution
molar mass
the mass in grams of one mole of any pure substance
molar volume
for a gas, the volume that one mole occupies; 22.4 at one mole
the SI base unit used to measure the amount of a substance
a neutral subatomic particle in an atoms nucleus that has a mass nearly equal to that of a proton
the vertical column of elements in the periodic table
the splitting of a nucleus into smaller, more stable fragments
the process of binding smaller atomic nuclei into a single larger and more stable nucleus
noble gas configuration
electron configuration in which you incorporate the noble gas to replace a group of configurations
neutralization reaction
a reaction in which an acid and base react in aqueous solution to produce a salt and water
elements on the right side of periodic table; generally dull gases, brittle solids, and poor conductors of heat and electricity
octet rule
states that atoms lose, gain, or share electrons in order to acquire a full set of eight valence electrons
oxidation number
the positive or negative charge of a monatomic ion
Pauli exclusion principle
states that a maximum of two electrons may occupy a single atomic orbital, but only if the electrons have opposite spins
percent yield
the ratio of actual yield to theoretical yield expressed as a %; actual/theoretical x 100
percent error
the ratio of an error to an accepted value
the negative logarithm of the hydrogen ion concentration of a solution; 1-14; 7 is neutral; 0-6=acid; 8-14=base
a horizontal row of elements in the periodic table
physical change
a type of change that alters the physical properties of a substance but does not change its composition
physical property
A characteristic of a matter that can be observed without changing the samples composition; ex. density, color, taste, etc
a particle of electromagnetic radiation with no mass that carries a quantum of energy
polar covalent
a type of bond that forms when electrons are not shared equally
a solid produced during a chemical reactin in a solution
refers to how close a series of measurements are to one another; precise measurements show little variation over a series of trials but may not be accurate
a substance formed during a chemical reaction
a subatomic particle in an atoms nucleus with a positive charge a 1+
the starting substance in a chemical reaction
excess reactant
a reactant that remains after a chemical reactant starts
contains the maximum amount of dissolved solute for a give amount of solvent at a specific temp and pressure
single replacement reaction
a chemical reaction that occurs when the atoms of one element replace the atoms of another element in a compound
a substance dissolved in a solution
describes a substance that can be dissolved in a give solvent
the substance that dissolves a solute to form a solution
a uniform mixture that may contain solids, liquids, or gases
strong acid
an acid that ionizes completely in aqueous solution
strong base
a base that dissociates entirely into metal ions and hydroxide ions in aqueous solution
solid changes to directly to a gas w/o becoming liquid first
contains more dissolved solute than a saturated solution at the same temperatrue
synthesis reaction
a chemical reaction in which two or more substances react to yield a single product
a measure of the average kinetic energy of the particles in a sample of matter
theoretical yield
the maximum amount of product that can be produced from a given amount of reactant
unsaturated solution
contains less dissolved solute for a given temp and pressure than a saturated solution
valence electrons
the electrons in an atoms outermost orbitals; determines the elements chem properties
the shortest distance between equivalent points on a continous wave
weak acid
an acid that ionizes only partially in dilute aqueous solution
weak base
a base that ionizaes only partially in dilute aqueous solution to form the conjugate acid of the base and hydroxide ion
actual yield
the amount of product actully produced when a chemical reaction is carried out in an experiment
a form of energy that flows from a warmer object to a cooler object
the formula to determine heat