Chapter 3 Flashcards
Acid
A substance that increases the hydrogen ion concentration of a solution
Adhesion
The clinging of one substance to another, such as water to plant cell walls by means of hydrogen bonds
Aqueous Solution
A solution in which water is the solvent
Base
A substance that reduces the hydrogen ion concentration of a solution
Calorie (cal)
The amount of heat energy required to raise the temperature of 1 g of water by 1°C; also the amount of heat energy that 1 g of water releases when it cools by 1°C. The Calorie (with a capital C) usually used to indicate the energy content of food, is a kilocalorie
Buffer
A solution that contains a weak acid and its corresponding base. A buffer minimizes changes in pH when acids or bases are added to the solution
Cohesion
The linking together of like molecules, often by hydrogen bonds
Heat of Vaporization
The quantity of heat a liquid must absorb for 1 g of it to be converted from the liquid to the gaseous state
Evaporative Cooling
The 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
Heat
Thermal energy in transfer from one body of matter to another
Hydration Shell
The sphere of water molecules around a dissolved ion
Hydrogen Ion
A single proton with a charge of 1+. The dissociation of a water molecule leads to the generation of a hydroxide ion and a hydrogen ion; in water, H+ is not found alone but associates with a water molecule to form a hydronium ion
Hydrophilic
Having an affinity for water
Hydronium Ion
A water molecule that has an extra proton bound to it; commonly represented as H+
Joule (J)
A unit of energy
Hydroxide Ion
A water molecule that has lost a proton
Hydrophobic
Having no affinity for water; tending to coalesce and form droplets in water
Kilocalorie (kcal)
A thousand calories; the amount of heat energy required to raise the temperature of 1kg of water by 1°C
Molarity
A common measure of solute concentration, referring to the number of moles of solute per liter of solution
Kinetic Energy
The energy associated with the relative motion of objects
Mole (mol)
The number of grams of a substance that equals its molecular or atomic mass in daltons; a mole contains Avogadro’s number of the molecules or atoms in question
Molecular Mass
The sum of the masses of all the atoms in a molecule; sometimes called molecular weight
Ocean Acidification
Decreasing pH of ocean waters due to absorption of excess atmospheric CO2 from the burning of fossil fuels
Polar Covalent Bond
A covalent bond between atoms that differ in electronegativity. The shared electrons are pulled closer to the more electronegative atom, making it slightly negative and the other atom slightly positive
Polar Molecule
A molecule (such as water) with and uneven distribution of charges in different regions of the molecule
Surface tension
A measure of how difficult it is to stretch or break the surface of a liquid. Water has a high surface tension because of the hydrogen bonding of surface molecules
Solvent
The dissolving agent of a solution. Water is the most versatile solvent known
Solute
A substance that is dissolved in a solution
Specific Heat
The amount of heat that must be absorbed or lost for 1 g of a substance to change its temperature by 1°C
Temperature
A measure in degrees of the average kinetic energy (thermal energy) of the atoms and molecules in a body of water
Thermal Energy
Kinetic energy due to the random motion of atoms and molecules; energy in its most random form
