Chapter 3

Question 1

what is cohesion?

Answer 1

hydrogen bonds holding water together

Question 2

what is surface tension

Answer 2

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

Question 3

what is adhesion?

Answer 3

the clinging of one substance to another

Question 4

what is thermal energy

Answer 4

the kinetic energy associated with the random movement of atoms or molecules

Question 5

what is temperature

Answer 5

the average kinetic energy of the molecules in a body of matter, regardless of veolume

Question 6

what is heat?

Answer 6

thermal energy in transfer from one body of matter to another

Question 7

what is a calorie

Answer 7

one unit of heat; the amount of heat it takes to raise the temperature of 1g of water by 1C

Question 8

what is a kilocalorie?

Answer 8

the amount of heat required to raise the temperature of 1 kilogram of water by 1C

Question 9

what is a joule?

Answer 9

0.239cal; one calorie = 4.184J

Question 10

what is specific heat?

Answer 10

the specific heat of a substance is defined as the amount of heat that must be absorbed or lost for 1g of that substance to change its temperature by 1degree C

Question 11

what is heat of vaporization?

Answer 11

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

Question 12

what is evaporative cooling

Answer 12

as a liquid evaporates, the surface of the liquid that remains cools down

Question 13

what is a solution

Answer 13

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

Question 14

what is a solvent

Answer 14

dissolving agent of a solution

Question 15

what is a solute

Answer 15

substance that is dissolved

Question 16

what is an aqueous solution

Answer 16

a solution in which the solute is dissolved in water; water is the solvent

Question 17

what is a hydration shell?

Answer 17

the sphere of water molecules around each dissolved ion

Question 18

what is a hydrophillic substance?

Answer 18

water-loving

Question 19

what is a hydrophobic substance

Answer 19

water fearing

Question 20

what is molecule mass

Answer 20

the sum of the masses of all the atoms in a molecule

Question 21

what is a mol

Answer 21

Avogadros number; 6.02x10^23

Question 22

what is molarity

Answer 22

the number of mols of solute per liter of solution

Question 23

what is a hydrogen ion

Answer 23

H+ (single protons with a charge of 1+)

Question 24

what is a hydroxide ion

Answer 24

a water molecule that lost a proton (charge of 1-); OH-

Question 25

what is a hydronium ion

Answer 25

(H3O+); water molecule+ proton

Question 26

what is an acid

Answer 26

substance that increases the hydrogen ion concentration of a solution. pH less than 7

Question 27

what is a base

Answer 27

a substance that reduces the hydrogen ion concentration; pH above 7

Question 28

what is a buffer

Answer 28

a substance that minimizes changes in the concentrations of H+ and OH- in a solution

Question 29

what is ocean acidification

Answer 29

when CO2 dissolves in seawater, it reacts with carbonic acid, which lowers the ocean pH.