Chapter 2 & 3 - The Chemical Context of Life & Water and Life

Question 1

anything that takes up space and has mass

Answer 1

Matter

Question 2

substance that cannot be broken down to other substances by chemical reactions

Answer 2

element

Question 3

substance consisting of two or more different elements combined in a fixed ratio

Answer 3

compound

Question 4

elements that an organism needs to live a healthy life and reproduce

Answer 4

essential elements

Question 5

required by an organism in only minute quantities

Answer 5

trace elements

Question 6

smallest unit of matter that still retains the properties of an element

Answer 6

atom

Question 7

number of protons, which is unique to each element

Answer 7

atomic number

Question 8

total number of protons and neutrons in the nucleus of an atom

Answer 8

mass number

Question 9

the total mass of an atom

Answer 9

atomic mass

Question 10

different atomic forms of the same element

Answer 10

isotopes

Question 11

the nucleus decays spontaneously, giving off particles and energy

Answer 11

radioactive isotope

Question 12

fixed rate at which a parent isotope decays into its daughter isotope (the time it takes for 50% of the parent isotope to decay)

Answer 12

half-life

Question 13

process where scientists measure the ratio of different isotopes and calculate how many half-lives have passed since an organism was fossilized or a rock was formed

Answer 13

radiometric dating

Question 14

the capacity to cause change, by doing work

Answer 14

energy

Question 15

the energy that matter possesses because of its location or structure

Answer 15

potential energy

Question 16

outer electrons in an atom

Answer 16

valence electrons

Question 17

the outermost electron shell

Answer 17

valence shells

Question 18

the 3D space where an electron is found 90% of the time

Answer 18

orbital

Question 19

interactions usually result in atoms staying close together, held by attractions

Answer 19

chemical bonds

Question 20

sharing of a pair of valence electrons by two atoms

Answer 20

covalent bonds

Question 21

two or more atoms held together by covalent bonds

Answer 21

molecule

Question 22

a pair of shared electrons

Answer 22

single bond

Question 23

bonding capacity of an atom (equals number of electrons required to complete the atoms’s outermost shell

Answer 23

valence

Question 24

the attraction of a particular atom for the electrons of a covalent bond

Answer 24

electronegativity

Question 25

bond where electrons are shared equally in a covalent bond because they have the same electronegativity

Answer 25

nonpolar covalent bond

Question 26

bond where an atom is bonded to a more electronegative atom, the electrons are not shared equally

Answer 26

polar covalent bond

Question 27

oppositely charged atoms (or molecules)

Answer 27

ions

Question 28

positively charged ion

Answer 28

cation

Question 29

negatively charged ion

Answer 29

anion

Question 30

bond where cations and anions attract each other

Answer 30

ionic bond

Question 31

compounds formed by ionic bonds

Answer 31

ionic compounds or salts

Question 32

noncovalent attraction between a hydrogen and an electronegative atom

Answer 32

hydrogen bond

Question 33

individually weak and occur only when atoms and molecules are very close together

Answer 33

van der Waals interactions

Question 34

the making and breaking of chemical bonds, leading to changes in the composition of matter

Answer 34

chemical reactions

Question 35

starting materials in a chemical reaction

Answer 35

reactants

Question 36

resulting materials in a chemical reaction

Answer 36

products

Question 37

the point at which the reactions offset one another exactly

Answer 37

chemical equilibrium

Question 38

molecule where its overall charge is unevenly distributed

Answer 38

polar molecule

Question 39

hydrogen bonds hold the substance together

Answer 39

cohesion

Question 40

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

Answer 40

surface tension

Question 41

clinging of one substance to another

Answer 41

adhesion

Question 42

energy of motion

Answer 42

kinetic energy

Question 43

kinetic energy associated with the random movement of atoms or molecules (TOTAL kinetic energy)

Answer 43

thermal energy

Question 44

represents the AVERAGE kinetic energy of the molecules in a body of matter, regardless of volume

Answer 44

temperature

Question 45

thermal energy in transfer from one body of matter to another

Answer 45

heat

Question 46

amount of heat it takes to raise the temp of 1g of water by 1 degree Celsisus

Answer 46

calorie (cal)

Question 47

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

Answer 47

specific heat

Question 48

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

Answer 48

heat of vaporization

Question 49

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

Answer 49

evaporative cooling

Question 50

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

Answer 50

solution

Question 51

dissolving agent of a solution

Answer 51

solvent

Question 52

substance that is dissolved

Answer 52

solute

Question 53

solution in which the solute is dissolved in water

Answer 53

aqueous solution

Question 54

sphere of water molecules around each dissolved ion

Answer 54

hydration shell

Question 55

any substance that has an affinity for water (WATER LOVING)

Answer 55

hydrophilic

Question 56

substances that are nonionic and nonpolar that seem to repel water

Answer 56

hydrophobic

Question 57

sum of the masses of all the atoms in a molecule

Answer 57

molecular mass

Question 58

represents an exact number of objects (6.02 x 10 ^23)

Answer 58

mole (mol)

Question 59

the number of moles of solute per liter of solution

Answer 59

molarity

Question 60

a single proton with a charge of 1+

Answer 60

hydrogen ion (H+)

Question 61

when a water molecule loses a proton and now has a charge of 1 -

Answer 61

hydroxide ion (OH--)

Question 62

the proton binds to the other water molecule, which now has 3 hydrogens

Answer 62

hydronium ion (H3O-)

Question 63

substance that increases the hydrogen ion concentration of a solution

Answer 63

acid

Question 64

a substance that reduces the hydrogen ion concentration of a solution

Answer 64

base

Question 65

The _____ of a solution is defined as the negative logarithm (base 10) of the H+ ion concentration

Answer 65

pH

Question 66

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

Answer 66

buffer

Question 67

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

Answer 67

ocean acidification