CH3: WATER AND LIFE

Question 1

overall charge is unevenly distributed

Answer 1

polar molecule

Question 2

phenomenon where H-bonds hold substances together

Answer 2

cohesion

Question 3

the clinging of one substance to another (i.e. capillary action)

Answer 3

adhesion

Question 4

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

Answer 4

surface tension

Question 5

energy of motion (faster = more of this)

Answer 5

kinetic energy

Question 6

kinetic energy associated with the random movement of atoms or molecules, depends in part on the matter’s volume

Answer 6

thermal energy

Question 7

measure of energy that represents the average kinetic energy of the molecules in a body of matter, regardless of volume

Answer 7

temperature

Question 8

thermal energy in transfer from one body of matter to another

Answer 8

heat

Question 9

measures the amount of heat it takes to raise the temp of 1g of 1mL of water by 1*C

Answer 9

calorie (cal)

Question 10

1,000 calis the quantity of heat required to raise the temp of 1kg of water by 1*C

Answer 10

kilocalorie (kcal)

Question 11

energy unit; J = 0.239 cal; one cal = 4.184J

Answer 11

joule (J)

Question 12

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

Answer 12

specific heat

Question 13

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

Answer 13

heat of vaporization

Question 14

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

Answer 14

evaporative cooling

Question 15

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

Answer 15

solution

Question 16

dissolving agent of a solution

Answer 16

solvent

Question 17

substance that is dissolved

Answer 17

solute

Question 18

the solute is dissolved in water (water is the solvent)

Answer 18

aqueous solution

Question 19

sphere of water molecules around each dissolved ion (can dissolve nonionic polar molecules; i.e. proteins, etc)

Answer 19

hydration shell

Question 20

sum of the masses of all the atoms in a molecule in daltons (in grams = 6.02x10^23 molecules or 1 mol)

Answer 20

molecular mass

Question 21

represents an exact number of objects (avogradro’s number: 6.02x10^23)

Answer 21

mole (mol)

Question 22

the number of moles of solute per liter of solution (moles/L)

Answer 22

Molarity (M)

Question 23

single proton; +1 charge; does not exist on its own in aq solutions

Answer 23

Hydrogen ion (H+)

Question 24

charge 1- (negative ion when H2O dissociates)

Answer 24

hydroxide ion (OH-)

Question 25

proton binds to the other water molecule (often represented as H+)

Answer 25

hydronium ion (H3O+)

Question 26

substance that increases the H+ conc of a solution

Answer 26

acid

Question 27

substance that reduces the H+ conc of a solution

Answer 27

base

Question 28

pH > 7

Answer 28

base

Question 29

pH < 7

Answer 29

acid

Question 30

negative log (base 10) of H+ conc

Answer 30

pH

Question 31

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

Answer 31

buffer

Question 32

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

Answer 32

ocean acidification