Chem final-vocab

mass

the measure of the amount of matter

matter

anything that has mass and takes up space

atom

the smallest unit of an element that maintains the chemical identity of that element

element

a pure substance that cannot be broken down into simpler, stable substances and is made of one type of atom

compound

a substance that can be broken down into simple stable substances; made from 2 or more elements that are chemically bonded

extensive properties

properties which depend on the amount of matter that is present(volume, mass, energy)

intensive properties

properties which do not depend on the amount of matter present(melting/boiling point, density, ability to conduct electricity)

physical property

a characteristic that can be observed or measured without changing the identity of the substance

physical change

A change in a substance that does not involve a change in the identity of the substance

change of state

a physical change of a substance from one state to another

solid

definite volume and definite shape

liquid

definite volume but indefinite shape

gas

indefinite volume and shape

plasma

physical state of matter in which atoms lose most of their electrons(negativity changed particles that move about the atomic nucleus)

chemical property

relates to a substance’s ability to undergo changes that transform it into different substances

chemical change/reaction

change in which 1 or more substances are converted into different substances

reactants

substances that react in a chemical change

products

substances that are formed by the chemical change

groups/families

vertical columns of the periodic table

periods

horizontal row of elements in the periodic table

metal

an element that is a good electrical conductor and a good heat conductor

nonmetal

an element that is a poor conductor of heat and electricity

metalloid

an element that has some characteristics of metals and some characteristics of nonmetals

law of conservation of mass

states that mass is neither created nor destroyed during ordinary chemical reactions or physical changes

law of definite proportions

the fact that a chemical compound contains the same elements in exactly the same proportions by mass regardless of the size of the sample or source of the compound

law of multiple proportions

if 2 or more different compounds are composed of the same 2 elements, then the ratio of the masses of the 2nd element combined with a certain mass of the 1st element is always a ratio of small whole numbers

atom

the smallest particle of an element that retains the chemical properties of that element

plum pudding model

theory that negative electrons were spread evenly throughout the positive charge of the rest of the atom

alpha particles

fast, positively charged atoms with about 4x the mass of a hydrogen atom

nuclear forces

short-range proton-neutron, proton-proton, and neutron-neutron forces holding the nuclear particles together

atomic number

shows the number of protons in each atom of an element

isotopes

atoms of the same element that have different masses

mass number

the total number of protons and neutrons that make up the nucleus of an isotope

nuclide

general term for a specific isotope of an element

average atomic mass

is the weighted average of the atomic masses of the naturally occurring isotopes of an element

mole

the amount of a substance that contains as many particles are there are atoms is exactly 12g of carbon- 12 (unit)

avogadro’s number

6\.022 x 10^23 (number of particles in 1 mol)

molar mass

the mass of one mole of a pure substance

periodic law

the physical and chemical properties of the elements are periodic functions of their atomic numbers

periodic table

an arrangement of the elements in order of their atomic numbers so that elements with similar properties fall ikn the same column or group

chemical bond

a mutual electrical attraction between the nuclei and valence electrons of different atoms that binds the atoms together

ionic bonding

chemical bonding that results from the electrical attraction between cations and anions

covalent bonding

results from the sharing of electron pairs between 2 atoms

nonpolar-covalent bond

a covalent bond in which the bonding electrons are shared equally by the bonded atoms, resulting in a balanced distribution of electrical charge

polar-covalent bond

a covalent bond in which the bonded atoms have an unequal attraction for shared electrons

polar

bonds with an uneven distribution of charge

molecule

a neutral group of atoms that are held together by covalent bonds

molecular compound

a chemical compound whose simplest units are molecules

chemical formula

indicates the relative number of atoms of each kind in a chemical compound by using atomic symbols and numerical subscripts

molecular formula

shows the types and number of atoms combined in a single molecule of a molecular compound

bond energy

the energy required to break a chemical bond and form neutral isolated atoms

electron-dot notation

an electron-configuration notation in which only the valence electrons of an atom of a particular element are shown, indicated by dots placed around element’s symbol

single bond

a covalent bond in which one pair of electrons is shared between 2 atoms

multiple bonds

multiple covalent bonds (double/triple )

ionic compound

composed of positive and negative ions that are combined so that the numbers of positive and negative charges are equal

formula unit

the simplest collection of atoms from which an ionic compound’s formula can be written

lattice energy

the energy released when one mole of an ionic crystalline compound is formed from gaseous ions

polyatomic ion

a charged group of covalently bonded atoms

metallic bonding

the chemical bonding that results from the attraction between metal atoms an d the surrounding sea of electrons

malleability

the ability of a substance to be hammered or beaten into thin sheets

ductility

the ability of a substance to be drawn, pulled, or extruded through a small opening to produce a wire

monatomic ions

ions formed from a single atom

binary compounds

compounds composed of 2 elements

nomenclature

naming system of binary ionic compounds

oxyanions

polyatomic ions that contain oxygen

oxidation states/numbers

assigned to atoms composing the compound/ion in order to indicate general distribution of electrons among the bonded atoms in a molecular compound or a polyatomic ion

kinetic-molecular theory

theory based on the idea that particles of matter are always in motion.

ideal gas

a hypothetical gas that perfectly fits all the assumptions of the kinetic-molecular theory

elastic collision

collision in which there is no net loss of total kinetic energy

diffusion

process by which particles of a gas spread out spontaneously and mix with other gases

effusion

a process by which gas particles pass through a tiny opening into a vacumn

real gas

a gas that does not behave completely according to the assumptions of the kinetic-molecular theory

fluid

a substance that can flow and therefore take shape of it’s container

surface tension

a force that tends to pull adjacent parts of a liquid’s surface together, thereby decreasing surface area to the smallest possible size

capillary action

the attraction of the surface of a liquid to the surface of a solid, is a property closely related to surface tension

vaporization

the process by which a liquid or solid changes to a gas

evaporation

the process by which particles escape from the surface of a nonboiling liquid and enter the gas state

crystalline solids

solid which consists of crystals

crystals

a substance in which the particles are arranged in an orderly, geometric, repeating pattern

amorphous solid

solid in which the particles are arranged randomly

supercooled liquids

substances that retain certain liquid properties even at temperatures at which they appear to be solid

crystal structure

the total 3-dimensional arrangement of particles of a crystal

unit cell

the smallest portion of a crystal lattice that shoes the 3-dimensional pattern of the entire lattice

ionic crystal

crystal structure consists of positive and negative ion s arranged in a regular pattern; hard and brittle and good insulators

covalent network crystals

crystal structure consists of each atom being covalently bonded bonded to it’s nearest neighboring atoms; hard/brittle and nondonductors

metallic crystals

crystal structure consists of metal cations surrounded by sea of delocalized valence electrons; high conductivity

covalent molecular crystals

crystal structure consists of covalently bonded molecules held together by intermolecular forces; relatively soft and good insulators

phase

any part of a system that has uniform composition and properties

condensation

the process by which a gas changes to a liquid

equilibrium

a dynamic condition in which 2 opposing changes occur at equal rates in a closed system

equilibrium vapor pressure

the pressure exerted by a vapor in equilibrium with its corresponding liquid at a given temperature

volatile liquids

liquids that evaporate readily, have relatively weak forces of attraction between their particles

soluble

we mean capable of being dissolved

solution

a homogenous mixture mixture of 2 or more substances uniformly dispersed throughout a single phrase

solvent

the dissolving medium in a solution

solute

the substance dissolved in a solution

suspension

the particles in a solvent are so large that they settle out unless the mixture is constantly stirred or agitated

colloids

particles that are intermediate in size between those in solutions and suspensions from mixture known as colloidal dispersions

electrolyte

a substance that dissolves in water to give solution that conducts electric current

nonelectrolyte

a substance that dissolves in water to give a solution that does not conduct an electric current