Env Chem Exam 3

Front 1

left of equation

Back 1

reactants

Front 2

right of equation

Back 2

products

Front 3

(s)

Back 3

solid

Front 4

(l)

Back 4

liquid

Front 5

(g)

Back 5

gas

Front 6

(aq)

Back 6

aqueous (in water)

Front 7

balancing chem equations

Back 7

must have same number of element on both sides of equation

Front 8

isotopic mass

Back 8

mass of an isotope of an element

Front 9

atomic mass

(weight)

Back 9

AVERAGE of the masses of the naturally occurring isotopes of an element
(weighted according to their abundance)

Front 10

molecular / formula mass

Back 10

sum of atomic masses of the atoms (or ions) in a molecule

Front 11

mole

Back 11

amount of a substance that contains the same number of entities as there are atoms
in 12 g of carbon-12

(entities = atoms / molecules / formula units etc)

Front 12

molar mass

Back 12

mass of 1 mol of a substance
(different for every compound)

numerically equivalent to formula mass

units: g/mol

used to convert between moles and mass

Front 13

stoichiometry

Back 13

relationship between reactants and products in chem reaction

Front 14

kinetic - molecular theory

postulate 1

Back 14

volume of gas particle is so small compared to volume of container -- they're considered to have mass - but NO VOLUME

(particle volume)

Front 15

kinetic - molecular theory

postulate 2

Back 15

gas particles are in constant, random, straight line motion, except when they colllide w eachother or container walls

(particle motion)

Front 16

kinetic -molecular theory

postulate 3

Back 16

collisions are elastic -- therefore total kinetic energy of particles is constant

(particle collisions)

Front 17

gas laws

1

Back 17

all matter composed of tiny discrete particles aka "molecules"

Front 18

gas laws

2

Back 18

molecules in a gas are in rapid constant, straight line, motion

Front 19

gas laws

3

Back 19

gas molecules tiny compared to distance between molecules

Front 20

gas laws

4

Back 20

little atttraction between gas molecules

Front 21

gas laws

5

Back 21

energy conserved during collisions of molecules

Front 22

gas laws

6

Back 22

temp measures avg kinetic energy of gas molecule

Front 23

boyle' law

Back 23

at constant Temp, volume varies inversely with pressure

Front 24

charles' law

Back 24

at constant P, the volume of fixed amt of gas = directly proportional to its absolute T

Front 25

molar volume

Back 25

volume occupied by 1 mol of gas

Front 26

standard temp / pressure

(STP)

Back 26

1 atm pressure & 0*C

1 mole of gas has volume of 22.4 L

Front 27

solution

Back 27

homogeneous mixture of 2 substances

Front 28

solute

Back 28

whats being dissolved

Front 29

solvent

Back 29

whats doing the dissolving

Front 30

aqueous solution

Back 30

water is solvent

Front 31

soluble

Back 31

a decent quantity dissolves

Front 32

insoluble

Back 32

very little, if any, quantity dissolves

Front 33

dilute solution

Back 33

little solute
lot of water

Front 34

concentrated solution

Back 34

lots of solute in solvent

Front 35

molarity

Back 35

amount of solute (in moles) per liter solution

Front 36

if both solute and solvent are liquids

Back 36

use percent by volume

Front 37

convert molecular formula to lewis structure

Back 37

sum valence electrons from all atoms

(anion - add e for each (-) charge
cation - subtract e for each (+) charge z

write symbols and show connection with single bond
(central atom least electronegative)

complete octects of atoms bonded to central atom (H can only have 2)

if not enough e to give central atom octect, try double bonds

Front 38

free radicals

Back 38

odd number of e's

-one unpaired e

-very radioactive

Front 39

common radical?

Back 39

nitrous oxide (NO)

key component in smog

Front 40

molecular shape

Back 40

determines reactive, chem, and phys properties

-important in biological systems

**draw e dot diagram to predict shape of molecule .... look @ central atom

Front 41

valence shell electron pair repulsion theory

Back 41

e pairs arrange themselves to min repulsion

Front 42

determine shape of molecule

Back 42

1. draw e dot strucutre

2. count # of bonding / nonbonding pairs

3. determine # of e sets

4. sketch shape

Front 43

polar molecules

Back 43

seperate centers of + & - charge

Front 44

states of matter

Back 44

solid liquid gas

Front 45

intra molecular forces

Back 45

bonding forces

exist w/i the molecule

influence CHEMICAL properites of the substance

Front 46

inter molecular forces

Back 46

non bonding forces

exist BETWEEN molecules

determine PHYSICAL Properties of substnace

Front 47

Hydrogen Bond

Back 47

dipole-dipole intermolecular force

may occur when H atom in molecule bound to highly EN atom w/ lone pairs of e's -== is attracted to lone pairs of another molecule

elements this EN = N, O, F

Front 48

polarizability of Ptable

Back 48

increases down group
(size increases and larger e clouds are further from nucleus)

decreases from L to R across period
(shrink atomic size and holds e's tighter)

Front 49

polarizability of cat/an- ions

Back 49

cations - less polarizable than parent atom bc SMALLER

anions = more polarizable than parent atom bc LARGER

Front 50

polarizability and dispersion

Back 50

directlyrelated

down group - p increases
down group - d increases

down group:
BOILING PTS INCREASE
MOLAR MASS inCREASE