Bio Notes Pgs. 18-30

Front 1

two components of chemical evolution

Back 1

pattern component & process component

Front 2

pattern component

Back 2

small molecules & complex carbon-containing substances are required for life

Front 3

process component

Back 3

early on, simple chemical compounds combined to form more complex carbon-containing substances before life

Front 4

when is an atom electrically neutral?

Back 4

when # of protons and electrons are the same

Front 5

what varies in an element?

Back 5

# of neutrons can vary to form different masses but if diff. number of protons it is a different element

Front 6

isotopes

Back 6

forms of an element w/ different number of neutrons

Front 7

atomic weight

Back 7

average weight of all isotopes

Front 8

radioactive isotope

Back 8

nucleus eventually decays because it is unstable, and it releases radiation energy

Front 9

how many electrons can an orbital hold

Back 9

two

Front 10

electron shells

Back 10

numbered to show how far/close they are to nucleus

Front 11

chemical bond

Back 11

attractions that bind atoms together

Front 12

covalent bond

Back 12

strong attraction where two atoms share one or more pairs of electrons

Front 13

molecules

Back 13

substances held together by covalent bond

Front 14

electronegativity

Back 14

how tightly an atom holds electrons in a covalent bond

Front 15

factors that affect electronegativity

Back 15

# of protons in the nucleus & distance between nucleus and valance shell

Front 16

ionic bond

Back 16

electrons are transferred from one atom the other, gives resulting atoms a full outermost shell

Front 17

ion

Back 17

an atom/ molecule that carries a full charge, rather than a partial charge than results from a polar covalent bond

Front 18

cation

Back 18

positively charged ion (loses an electron)

Front 19

anion

Back 19

negatively charged ion (gains an electron)

Front 20

solvent

Back 20

an agent for dissolving substances

Front 21

cohesion

Back 21

attraction between like molecules (staying together)

Front 22

adhesion

Back 22

attraction between unlike molecules

Front 23

molecular weight

Back 23

sum of the atomic weights of all the atoms in a molecule

Front 24

mole

Back 24

6.022 x 10(23) ---- the mass of one mole of any substance= the molar weight expressed in grams

Front 25

molarity

Back 25

# of moles of substance per liter of solution

Front 26

hydrophilic

Back 26

water-loving

Front 27

hydrophobic

Back 27

water-fearing

Front 28

cohesion

Back 28

attraction between like molecules

Front 29

adhesion

Back 29

attraction between unlike molecules

Front 30

surface tension

Back 30

when water molecules on the surface have no other water molecules above them to form a hydrogen bond so they are more attracted to the molecules below them

Front 31

specific heat

Back 31

amount of energy required to raise the temperature of 1 gram of a substance by 1 degree celcius

Front 32

heat of vaporization

Back 32

energy required to change 1 gram of it from a liquid to a gas

Front 33

acids

Back 33

substances that give up protons during chemical reactions and raise the hydronium ion concentration in water

Front 34

bases

Back 34

ions that acquire protons during chemical reactions and lower the hydronium ion concentration of water

Front 35

molarity

Back 35

number of moles of the substance present per liter of solution

Front 36

buffers

Back 36

compounds that minimize changes in ph

Front 37

endothermic

Back 37

heat is absorbed during the process of turning into a gas

Front 38

exothermic

Back 38

heat is released during the process of turning into a liquid

Front 39

first law of thermodynamics

Back 39

energy is conserved. it cannot be created or destroyed, but it can be transferred or transformed

Front 40

photons

Back 40

packets of light energy

Front 41

hydrophobic

Back 41

do not interact with water

Front 42

hydrophilic

Back 42

interact readily with water

Front 43

poop

Back 43

poop