polar molecule
A molecule in which one side of the molecule is slightly negative and the opposite side is slightly positive due to unequal sharing of electrons.
cohesion
the intermolecular force, due to hydrogen bonding, that holds together the molecules in liquid water
adhesion
clinging of one substance to another due to hydrogen bonding
surface tension
measure of how difficult it is to stretch or break the surface of a liquid (due to cohesion)
heat
total amount of kinetic energy due to the random motion of atoms or molecules in a body of matter
temperature
a measure of the intensity of heat in degrees, reflecting the average kinetic energy of the molecules
calorie (cal)
quantity of heat required to raise the temperature of 1 gram of water by 1 degree Celsius, (equals 4.184 J)
kilocalorie (kcal)
1000 calories, the amount of heat required to raise the temperature of one kilogram of water by one degree
joule (J)
another unit of energy or heat, equals 0.239 cal
specific heat
amount of heat that must be absorbed or lost for 1 g of that substance to change its temperature by 1 degree C
heat of vaporization
quantity of heat a liquid must absorb for 1 g of it to be converted from the liquid to the gaseous state
evaporative cooling
process in which the surface of an object becomes cooler during evaporation, a result of the molecules with the greatest kinetic energy changing from the liquid to the gaseous state
solution
a liquid that is a completely homogeneous mixture of two or more substances
solvent
a liquid substance capable of dissolving other substances
solute
the dissolved substance in a solution
aqueous solution
a solution in which water is the solvent
hydrophilic
having a strong affinity for water
hydrophobic
lacking affinity for water, "water-fearing
molarity
concentration measured by the number of moles of solute per liter of solvent
buffer
substance that minimizes changes in the concentration of H+ and OH- in a solution
acid
A substance that increases the Hydrogen ion (H+) concentration of a solution
base
A substance that reduces the Hydrogen ion (H+) concentration of a solution