AP Bio Vocab Quiz 1

pH

A measure of hydrogen ion concentration equal to -log [H1] and ranging in value from 0 to 14

hydroxyl group

A chemical group consisting of an oxygen atom joined to a hydrogen atom. Molecules possessing this group are soluble in water and are called alcohols

carboxyl group

A chemical group present in organic acids and consisting of a single carbon atom double-bonded to an oxygen atom and also bonded to a hydroxyl group

base

A substance that reduces the hydrogen ion concentration of a solution

cis-trans isomer

One of two or more compounds that have the same molecular formula and covalent bonds between atoms but differ in the spatial arrangements of their atoms owing to the inflexibility of double bonds; formerly called a geometric isomer

hydrogen ion

A single proton with a charge of 11. The dissociation of a water molecule (H2O) leads to the generation of a hydroxide ion (OH2) and a hydrogen ion (H1); in water, H1 is not found alone but associates with a water molecule to form a hydronium ion

buffer

A solution that contains a weak acid and its corresponding base. Minimizes changes in pH when acids or bases are added to the solution

structural isomer

One of two or more compounds that have the same molecular formula but differ in the covalent arrangements of their atoms

hydronium ion

A water molecule that has an extra proton bound to it; H3O1, commonly represented as H1

methyl group

A chemical group consisting of a carbon bonded to three hydrogen atoms. May be attached to a carbon or to a different atom

carbonyl group

A chemical group present in aldehydes and ketones and consisting of a carbon atom double-bonded to an oxygen atom

solution

A liquid that is a homogeneous mixture of two or more substances

specific heat

The amount of heat that must be absorbed or lost for 1g of a substance to change its temperature by 1 degree Celsius

adhesion

The clinging of one substance to another, such as water to plant cell walls, by means of hydrogen bonds, different substance

thermal energy

Kinetic energy due to the random motion of atoms and molecules; energy in its most random form

hydrophobic

Having no affinity for water; tending to coalesce and rom droplets in water

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 of vaporization

The quantity of heat a liquid must absorb for 1g of it to be converted from the liquid to the gaseous state

solvent

The dissolving agent of a solution.

molarity

A common measure of solute concentration, referring to the number of moles of solute per liter of solution

temperature

A measure in degrees of the average kinetic energy (thermal energy) of the atoms and molecules in a body of matter

organic compounds

A chemical compound containing carbon

hydrophilic

Having an affinity for water

heat

Thermal energy in transfer from one body of matter to another

hydrocarbon

An organic molecule consisting of only carbon and hydrogen

cohesion

The linking together of like molecules, often by hydrogen bonds, same substance

surface tension

A measure of how difficult it is to stretch or break the surface of a liquid

calorie

The amount of heat energy required to raise the temperature of 1g of water by 1 degree Celsius; also the amount of heat energy that 1g of water releases when it cools by 1 degree Celsius. The Calorie (with a capital C), usually used to indicate the energy content of food, is a kilocalorie

solute

A substance that is dissolved in a solution

polar molecule

A molecule (such as water) with an uneven distribution of charges in different regions of the molecule

hydration shell

The sphere of water molecules around a dissolved ion

hydroxide ion

A water molecule that has lost a proton; OH2

enantiomer

One of two compounds that are mirror images of each other and that differ in shape due to the presence of an asymmetric carbon

acid

A substance that increases the hydrogen ion concentration of a solution

sulfhydryl group

A chemical group consisting of a sulfur atom bonded to a hydrogen atom

amino group

A chemical group consisting of a nitrogen atom bonded to two hydrogen atoms; can act as a base in solution, accepting a hydrogen ion and acquiring a charge of 11

functional group

A specific configuration of atoms commonly attached to the carbon skeletons of organic molecules and involved in chemical reactions

adenosine triphosphate (ATP)

An adenine-containing nucleoside triphosphate that releases free energy when its phosphate bonds are hydrolyzed. This energy is used to drive endergonic reactions in cells

phosphate group

A chemical group consisting of a phosphorus atom bonded to four oxygen atoms; important in energy transfer

ocean acidification

The process by which the pH of the ocean is lowered (made more acidic) when excess CO2 dissolves in seawater and forms carbonic acid (H2CO3)