Biology Chapter 2

Question 1

Any substance in the universe that has mass and occupies space

Answer 1

Matter

Question 2

Extremely small particles that make up matter

Answer 2

Atom

Question 3

A positively charged subatomic particle, found in the nucleus of an atom; has a mass of 1 dalton

Answer 3

Proton

Question 4

A subatomic particle found in the nucleus of an atom, has no charge; has a mass of 1 dalton

Answer 4

Neutron

Question 5

A negatively charged subatomic particle that orbits around the nucleus of an atom; the mass is 1/2000 of a dalton

Answer 5

Electron

Question 6

What makes up the nucleus of an atom?

Answer 6

Proton and neutron

Question 7

What orbits the nucleus of an atom?

Answer 7

electron

Question 8

what measurement is used for the mass of an atom?

Answer 8

in daltons

Question 9

How many daltons does it take to equal 1 gram>

Answer 9

6.02 x 10^23 daltons

Question 10

the number of protons in an atom is called __

Answer 10

atomic number

Question 11

the sum of neutrons and protons in an atom is called __

Answer 11

atomic mass

Question 12

any substance that cannot be broken down into any other substance by ordinary chemical means

Answer 12

element

Question 13

atoms of the same element that have different number of neutrons

Answer 13

isotope

Question 14

an isotope that is unstable and tends to break up into smaller elements, this decay releases a lot of energy

Answer 14

Radioactive isotope

Question 15

the rate of decay for a radioactive substance is constant; this is the amount of time needed for 1/2 of the stating material to decay

Answer 15

Half-life

Question 16

There are ___ naturally occurring elements

Answer 16

92

Question 17

When an atom or molecule looses an electron

Answer 17

oxidation

Question 18

when an atom or molecule gains an electron

Answer 18

reduction

Question 19

How many electrons can be in an orbital?

Answer 19

2

Question 20

What is an orbital?

Answer 20

the space that an electron occupies

Question 21

True or False. Energy levels and orbitals are the same.

Answer 21

False

Question 22

electrons in the outermost energy level are __

Answer 22

valence electrons

Question 23

Describe the octet rule.

Answer 23

the rule that atoms tend to want to completely fill the outermost energy levels

Question 24

True or False. For most of the atoms important to life, the outermost energy level can contain no more 8 electrons.

Answer 24

True

Question 25

Elements possessing all 8 electrons in their outermost energy level is called __ or non reactive

Answer 25

inert

Question 26

List the noble gases.

Answer 26

helium, neon, argon, krypton, xenon, radon

Question 27

List the 5 most common elements found in the human body.

Answer 27

Carbon, Hydrogen, Oxygen, Nitrogen, Calcium

Question 28

atoms where the number of electrons does not equal the number of protons; changing the number of electrons

Answer 28

ions

Question 29

an atom with more protons than electrons; has a net positive charge

Answer 29

cation

Question 30

an atom with more electrons; has a net negative charge

Answer 30

anion

Question 31

a stable association of atoms held together by energy

Answer 31

molecule

Question 32

a molecule containing more than one type of atom

Answer 32

compound molecule

Question 33

a bond between atoms resulting from attraction from oppositely charged atoms, or the sharing of one or more pairs of electrons between atoms

Answer 33

chemical bond

Question 34

a bond resulting from the attraction of oppositely charged ions

Answer 34

ionic bond

Question 35

a bond resulting from the sharing of one or more pairs of electrons between 2 atoms

Answer 35

covalent bonds

Question 36

List the different factor that influence the extent of chemical reactions.

Answer 36

Temperature (increases rate), concentrations of reactants & products (more molecules=increase rate), catalyst (enzymes)

Question 37

are all proteins that are used in the human body in order for a chemical reaction to occur

Answer 37

enzyme

Question 38

is a measure of the affinity for electrons

Answer 38

electronegativity

Question 39

Atoms with ___ electronegativity want electrons around them, whereas atoms with ___ electronegativity do not want electrons around them.

Answer 39

high; low

Question 40

any molecule that has an uneven charge distribution across it

Answer 40

polar molecule

Question 41

any molecule that has an even charge distribution across it.

Answer 41

non polar molecule

Question 42

when water molecules stick to other water molecules

Answer 42

cohesion

Question 43

when water molecules stick to other non water molecules

Answer 43

adhesion

Question 44

Give an example of cohesion in water properties.

Answer 44

Surface tension- when you have an interface between air and water, all the hydrogen bonds in the water face downward making molecules stick together

Question 45

Give an example of adhesion in water properties.

Answer 45

Capillary action- the attraction of water to substances that have electrical charges on their surface is responsible`

Question 46

the amount of heat required to change one gram of substance one degree in water properties

Answer 46

specific heat

Question 47

the amount of heat required to change one gram of liquid to gas

Answer 47

heat of vaporization

Question 48

the evaporation of water from a surface releases lots of heat energy, which cools the surface

Answer 48

evaporative cooling

Question 49

Water is a strong ___ because of its polar nature.

Answer 49

solvent

Question 50

Either the hydrogen end or the oxygen end in a water molecule will surround any molecule that has any polarity or is ionic, which is called

Answer 50

hydration shell

Question 51

Property of water- any non polar molecules that are put into water are going to be excluded by the water. This action forces the non polar molecules together.

Answer 51

hydrophobic exclusion

Question 52

water fearing; does not mix with water; non polar molecules

Answer 52

hydrophobic

Question 53

water loving; mixes with water; polar molecules

Answer 53

hydrophilic

Question 54

weight in grams of the sum of atomic masses

Answer 54

mole

Question 55

concentration of H+ in water is called

Answer 55

molar concentration

Question 56

a change in the pH value is a __fold change in concentration

Answer 56

10

Question 57

a pH of 7 is __

Answer 57

neutral

Question 58

any substance that dissociates in water to increase the H+

Answer 58

acid

Question 59

any substance that combines with H+ to reduce the H+ in water

Answer 59

base

Question 60

Acids increase the ___, meaning the molar concentration is __ to the solution, this causes a drop in the __.

Answer 60

H+, higher, pH

Question 61

a substance that acts as a reservoir for hydrogen ions; prevents changes in pH

Answer 61

buffers