CH3: WATER AND LIFE Flashcards
overall charge is unevenly distributed
polar molecule
phenomenon where H-bonds hold substances together
cohesion
the clinging of one substance to another (i.e. capillary action)
adhesion
a measure of how difficult it is to stretch or break the surface of a liquid
surface tension
energy of motion (faster = more of this)
kinetic energy
kinetic energy associated with the random movement of atoms or molecules, depends in part on the matter’s volume
thermal energy
measure of energy that represents the average kinetic energy of the molecules in a body of matter, regardless of volume
temperature
thermal energy in transfer from one body of matter to another
heat
measures the amount of heat it takes to raise the temp of 1g of 1mL of water by 1*C
calorie (cal)
1,000 calis the quantity of heat required to raise the temp of 1kg of water by 1*C
kilocalorie (kcal)
energy unit; J = 0.239 cal; one cal = 4.184J
joule (J)
the amount of heat that must be absorbed or lost for 1g of that substance to change its temperature by 1*C
how well a substance resists changing its temp when it absorbs or releases heat
specific heat
the quantity of heat a liquid must absorb for 1g of it to be converted from the liquid to the gaseous state
heat of vaporization
the surface of the liquid that remains behind cools down as a liquid evaporates
happens because the hottest molecules are most likely to leave as gas
evaporative cooling
a liquid that is a completely homogenous mixture of two or more substances
solution
dissolving agent of a solution
solvent
substance that is dissolved
solute
the solute is dissolved in water (water is the solvent)
aqueous solution
sphere of water molecules around each dissolved ion (can dissolve nonionic polar molecules; i.e. proteins, etc)
hydration shell
sum of the masses of all the atoms in a molecule in daltons (in grams = 6.02x10^23 molecules or 1 mol)
molecular mass
represents an exact number of objects (avogradro’s number: 6.02x10^23)
mole (mol)
the number of moles of solute per liter of solution (moles/L)
Molarity (M)
single proton; +1 charge; does not exist on its own in aq solutions
Hydrogen ion (H+)
charge 1- (negative ion when H2O dissociates)
hydroxide ion (OH-)
proton binds to the other water molecule (often represented as H+)
hydronium ion (H3O+)
substance that increases the H+ conc of a solution
acid
substance that reduces the H+ conc of a solution
base
pH > 7
base
pH < 7
acid
negative log (base 10) of H+ conc
pH
a substance that minimizes changes in the conc of H+ and OH- in a solution (fights changes in pH); most have a weak acid and weak base
accepts H+ when in excess and donate H+ when depleted
buffer
when CO2 dissolves in seawater, it reacts with water to form carbonic acid which lowers ocean pH
extra H+ reacts with carbonate ions to form bicarbonate ions
less carbonate ion for calcification to make calcium carbonate
ocean acidification
