WATER

Covalent

sharing of electrons

Polar covalent

unequal sharing of electrons due to difference in electronegativity

Nonpolar covalent

equal sharing of electrons

Electronegativity

ability of an atom to attract electrons

Electronegativity difference

difference of electronegativities between 2 atoms

Hydrogen bond

H bonded with N, O, F

Double Helix DNA

_______ is stabilized by Hydrogen bonds

Water

____ is medium for most chemical reactions

Hydrolysis

Addition of water to a Polymer to acquire monomer

Dehydration synthesis

Removal of water from monomer to acquire polymer

High Specific Heat

amount of heat needed to raise an amount of water by 1C or 1 unit

Polar Molecule

Unequal distribution of charges

Cohesive

stick to other water molecules

Adhesive

stick to surfaces

Polar Covalent Bond

electrons are unequally shared due to difference in electronegativity

Chemical behavior

how an atom would react based on interactions

Valence electron

interaction with atoms.

Found on the outermost shell of electron

Polar bond

covalent bond that has opposite partial charges on each side (one side partially positive, the other negative)

VSEPR Theory

Predicts the 3D shape of a molecule based on the rule that electron pairs repel and move away from each other

Lewis Structure

let us know which element must be placed in the MIDDLE

Ion-dipole Force

ion and a polar molecule

Hydrogen bond

attraction between special types of very polar molecules.

Hydrogen bond

force of attraction and more electronegative element: N, O, F

Dipole-dipole Forces

attraction between polar molecules (unequal sharing)

Dipole-induced forces

between polar and non-polar molecules (unequal + equal sharing)

London dispersion forces

between all molecules

Solubility

ability of solvent particles to interact with solute particles

Hydrophobic

water-fearing, nonpolar molecules

Hydrophilic

water-loving, dissolve in water

Amphipathic

both polar (hydrophilic) and nonpolar (hydrophobic) portions like sodium palmitate

Hydrophobic effect

Tendency of water to minimize contact with hydrophobic molecules

Diffusion

Movement of molecules from high concentration to low concentration passing through a semi-permeable membrane

Osmosis

Movement of water from high concentration to low concentration

Mole

Quantity of a substance containing Avogadro’s number

Molar mass

Mass in g/mol per substance

Equilibrium constant

expresses ionization of water

Chemical Equilibrium

Forward reaction and backward reaction proceed at the same rate

Acids

ph below 7

Base

ph above 7

Arrhenius

Acid: H+ donor

Base: OH- donor

Bronsted-Lowry

Acid: Proton donor

Base: Proton acceptor

Lewis

Acid: Electron pair acceptor

Base: Electron pair donor

Conjugate acid-base pairs

Acids and bases that are related by loss or gain of H+

Acid

behaves as a proton donor

Base

behaves as a proton acceptor

Amphoteric

water can act as an acid and base

acidity

the number of hydrogen ions present in a solution is a measure of the ____ of the solution

alkalinity

the number of hydroxyl ions present in a solution is a measure of the ____ of the solution

strong acids

_____ have a greater tendency to lose their proton and completely dissociate

weak acids

____ have a lesser tendency to lose their proton and do not readily dissociate in water

Acid dissociation constant (Ka)

strength of an acid

HIGHER Ka, LOWER Ka

____ = MANY molecules that ionize, STRONGER ACID

____ = LESS molecules to ionize

Buffer

resist changes in pH when moderate amounts of acids or bases are added

Buffer

Made with a WEAK ACID and soluble salt containing CONJUGATE BASE or a WEAK BASE and a soluble salt containing CONJUGATE ACID