A

• acetyl – a molecule containing 2-OR groups bonded to the same carbon
• acid – a substance that increases the concentration of H in an aqueous solution
• activation energy – the minimum amount of energy, specific to each chemical reaction, that the reactants must absorb from their surroundings in order for the reaction to occur
• alcohol – a compound containing an OH (hydroxyl) group bonded to a tetrahedral carbon atom
• aldehyde – a compound containing a carbonyl group bonded to a hydrogen: a CHO group
• allotrope – one of a set of different structural forms of an element, such as graphite, fullerene, and diamond forms of carbon
• alpha amino acids – the common 20 amino acids where the carboxyl and the amino group are both attached to the alpha carbon
• amine – an organic derivative of ammonia in which one, two or all three of the H atoms is replaced by a hydrocarbon chain
• amino acid – an organic compound containing an amino group and a carboxyl group
• anion – a negative ion
• Arrhenius acid – the earliest identification of acids as a particular class of compounds, with “acid” defined as any electrolyte that ionizes to give H ions when dissolved in water
• atmosphere – collection of gases that surround the earth
• atom – the smallest unit of an element that has the properties of that element
• atomic number – the number of protons in the nucleus of an atom
• atomic weight – a unit-less number expressing the mass of a particular element
• ATP – adenosine triphosphate
• axon – the long part of a nerve cell that comes out of the main cell body and eventually connects with another nerve cell or a tissue cell

B

• base – a substance that increases the concentration of OH- in an aqueous solution
• benzine -a colorless, volatile, flammable, liquid mixture of various hydrocarbons,obtained in the distillation of petroleum, and used in cleaning, dyeing,etc.
• beta sheet – also called the beta pleated sheet, this is another repeating secondary structure based on hydrogen bonding within and between peptide chains. The shape loops back on itself to give a flatter pleated appearance
• binary compound – a compound containing atoms of only two different elements
• body-centered cubic cell – a unit cell with one atom at the center of a cube and one atom at each of the 8 corners
• buffer – solution that contains significant concentrations of both members of a conjugate pair (weak acid/conjugate base or weak base/conjugate acid)

C

• Calvin cycle – the dark reactions of photosynthesis that produce glucose from CO2 and H2O by a cyclic process
• catalyst – a substance that, by lowering the activation energy of  chemical reaction, changes the rate at which the reaction proceeds, but is not itself consumed by the reaction
• cation – a positive ion
• chromosome – structures within the nucleus of eukaryotes that contain DNA and protein and that are replicated as units during mitosis
• colligative property – the properties that depend on the number of solute particles in solution but do not depend on the nature of the solute particles
• compound – a pure substance composed of two or more atoms of different elements
• condensation – a phase transition from gas to liquid
• Covalent bond – a shared pair of electrons
• Cis – a prefix meaning on the same side

D

• dehydration – elimination of a molecule of water from an alcohol; an OH is removed from one carbon and an H is removed from an adjacent carbon

 

• Dendrite – the hair-like projections that extend from the cell body of a nerve cell on the opposite side from the axon

 

• density – a measure of the compactness of matter

 

• Deposition – gas to solid

 

• Diatomic – consisting of two atoms

 

• Diffusion – the mixing of gases

 

• Dipeptide – a small protein molecule containing only two amino acids joined by a peptide linkage

 

• Dipolar molecule – a synonym for a polar molecule

 

• DNA – deoxyribonucleic acid – the macro molecule of heredity in eukaryotics and prokaryotics

E

• electrolyte – a substance that dissolves in water to yield a solution that conducts electricity

 

• electron – a negatively charged subatomic particle found outside the nucleus of all atoms

 

• electron affinity – the energy released when an atom in the gas phase accepts an electron

 

• electronegativity – the ability of an atom in a compound to draw electrons to itself

 

• element – a substance that cannot be separated into substances by chemical means

 

• enantiomere – molecules that are mirror images of each other

 

• endothermic – absorbs heat

 

• enthalpy – a change in heat

 

• entropy – a thermodynamic state function that describes how dispersed a system’s energy is

 

• enzyme – a biological catalyst that increases the rate of a chemical reaction by providing an alternative pathway with a lower activation energy

 

• equilibrium – a state in which forward and reverse processes are occurring at the same rate

 

• ester – a compound in which the H of a carboxyl group, RCOOH, is replaced by an OR group

 

• evaporation – a phase change from liquid to solid at a temperature below the boiling point

 

• exothermic – release of heat

F

• face-centered cubic cell – a cubic unit cell with one atom on each of the 6 faces and one atom at each of the 8 corners

 

• Farraday – *****

 

• fission – nuclear reaction in which heavy nucleus splits into lighter nuclei and energy is released

 

• functional group – an atom or group of atoms within a molecule that shows a characteristic set of chemical and physical properties

 

• fusion – nuclear reaction in which the nuclei are combined

G

• gas laws – equations that relate the volume of a gas sample to its other parameters: temperature, pressure, and number of moles

 

• gene – a segment of DNA that carries the base sequence that directs the synthesis of a particular protein

 

• glucogenic amino acid – an amino acid whose carbon skeleton can be used for the synthesis of glucose

 

• glycogenolysis – the hydrolysis of glycogen to glucose

H

• homeostasis – the process of maintaining the proper levels of nutrients and temperature of the blood

 

• hybridization – the mixing of atomic orbitals

 

• hydration –

 

• hydrocarbon – a compound that contains only hydrogen and carbon

 

• hydrogen bonding – a non-covalent interaction between a partial positive charge on a hydrogen bonded to an atom of high electronegativity and a partial negative charge on a nearby oxygen, nitrogen, or fluorine

 

• hydrolysis –  a reaction of a compound with water in which one or more bonds are broken

 

• hydrophilic– from the Greek meaning water loving

 

• hydrophobic – from the Greek meaning water hating

 

• hydroxyl group – an OH group bonded to a tetrahedral carbon atom

 

• ideal gas – hypothetical sample of gas whose pressure-volume-temperature behavior is predicted accurately by the ideal gas equation

 

• intermolecular forces – the attractive forces that hold particles together in the condensed phases

 

• ion – atom of molecule that has lost or gained one or more electrons, giving it a positive or negative charge

 

• ionic bonding – an electrostatic attraction that holds oppositely charged ions together in an ionic compound

 

• ionization – the process by which a molecular compound forms ions when it dissolves

 

• isomers – different compounds that have the same molecular formula

 

• isotonic – equal in concentration and osmotic pressure

 

• isotope – atoms that have the same atomic number but different mass numbers

J

• joule – SI unit of energy

K

• kelvin – the SI-based unit of temperature

 

• Kinetic energy – the energy that results from motion

L

• Lattice – a three dimensional array of cations and anions

 

• lattice energy – the amount of energy required to convert a mole of ionic solid to its constituent ions in the gas phase

 

• Lewis dot structure – a representation of covalent bonding in which shared electron pairs are shown either as dashes or pairs of dots between two atoms, and lone pairs are shown as pairs of dots on individual atoms

 

• ligand – a molecule or anion that can form coordinate bonds to a metal to form a coordination complex

 

• ligase – a class of enzymes that catalyzes a reaction joining two molecules

 

• lipase – an enzyme that catalyzes the hydrolysis of an ester bond between a fatty acid and  glycerol

 

• lone pair – a pair of valence electrons that are not involved in covalent bond formation

M

• mass – a measure of the amount of matter in an object or a sample

 

• matter – anything that occupies space and has mass

 

• molality(m) – the number of moles of solute dissolved in one kg of solvent

 

• molarity (M) – the number of moles of solute per liter of solution

 

• mole – an SI unit of measurement

 

• molecular formula – a chemical formula that gives the number of atoms in each element in a molecule

 

• molecular mass – the sum of the atomic masses of the atoms that make up a molecule

 

• molecule – a combination of two or more atoms in a specific arrangement held together by chemical bonds

 

• monomer – a small molecule that can be linked in large numbers to form a  large molecule

N

• neutron – an electrical neutral subatomic particle with a mass slightly greater than that of a proton

 

• newton(N) – the SI unit of force

 

• noble gases – elements in group 8A

 

• nucleotide – a structural unit consisting of a sugar bonded to both a cyclic-amine base and a phosphate group

 

• nucleus – the central core of the atom that contains the protons and the neutrons

O

• octet rule – atoms will lose, gain, or share electrons to achieve a noble gas electron configuration

 

• osmosis – the selective passage of solvent molecules thru a porous membrane from a more dilute solution to a more concentrated one

 

• osmotic pressure – the pressure required to stop osmosis

 

• oxidation – adding oxygen while losing electrons

P

• pascal (Pa) – the SI unit of pressure

 

• peptide – a short chain of amino acids linked via peptide bonds

 

• peptide bond –

 

• period – a horizontal row of the periodic table

 

• phenol – a compound that contains an OH bonded to a benzine ring

 

• polar – having non-uniform electron density

 

• product – a substance that forms in a chemical reaction

 

• prokaryote – an organism that has no true nucleus or organelles

 

• proton –

R

• radical – a chemical species with an odd number electrons

 

• reactant – a substance that is consumed in a chemical reaction

 

• redox reaction – a chemical reaction in which electrons are transferred from one reactant to another

 

• reduction – losing oxygen while gaining electrons

 

• RNA – ribonucleic acid – a type of nucleic acid consisting of nucleotide monomers of a nitrogenous base, ribose and phosphate

S

• salt bridge – an inverted U tube containing an inert electrolyte solution that maintains electrical neutrality in an electrochemical cell

 

• solubility – the maximum amount of solute that will dissolve in a given quantity of solvent at a specific temperature

 

• solute – the dissolved  substance in a solution

 

• solution – a homogeneous mixture consisting of a solvent and one or more solutes

 

• solvent – a substance in a solution that is present in the largest amount

 

• spectator ion – an ion that does not participate in the reaction and appears on both the reactant and the product side in the ionic equation

 

• stereo isomer – molecules that contain identical bonds but differ in the orientation of those bonds in space

 

• stoichiometry – the branch of chemistry that deals with measuring the quantities of reactants and products involved in the chemical reactions

 

• sublime/sublimation – from a solid to a gas

 

• substrate – the compound or compounds whose reaction is catalyzed by an enzyme

T

• titration – the gradual addition of a solution known of known concentration to another solution of unknown concentration until the chemical reaction between the two solutions is complete

 

• transcription – the process by which RNA polymerase synthesizes RNA from a DNA template

 

• transition metal – the elements in group 1B and groups 3B-8B

V

• valence electrons – the outermost electrons of an atom

 

• vaporization – a phase change from liquid to gas at the boiling point