Chem 1H Semes. 2 Cards

Front 1

formula for: avg. rate of a reaction (reaction rate)

Back 1

avg. rate= ^(quantity)/^t

Front 2

Collision Theory

Back 2

States that atoms, ions, and molecules must collide in order to react. (They must collide w/ correct orientation/they must have sufficient energy when colliding to form the activated complex)

Front 3

activated complex

Back 3

a temporary, unstable arrangement of atoms that may form products or may break apart to re-form reactants. (AKA transition state)

Front 4

activation energy

Back 4

the minimum amount of energy that reacting particles must have ot form the activated complex.

-it influences reacion rate (high Ea=few collisions will have enough energy to produce activated complex>reaction rate is low/ low Ea=more collisions will have enough energy to react, reaction rate will be higher)

Front 5

how is reaction rate affected with concentration?

Back 5

concentration increase=increased rate

concentration decreases=decreased rate

Front 6

how does surface area affect reaction rates?

Back 6

greater surface area=faster reaction

less surface area=slower reaction

Front 7

how does temp. affect reaction rate?

Back 7

increase temp. increases rate

Front 8

catalyst

Back 8

an enzyme , or a substance that increases teh rate of a chemical reaction without itself being consumed in teh reaction.

-not included in chem. equation

Front 9

inhibitor

Back 9

a substance that is the opposite of a catalyst

-slows down reaction rates/some prevent teh reaction from happening at all.

Front 10

heterogenoeous catalyst/homogenous catalyst

Back 10

it exists in a physical state different than that of the reaction it catalyzes
-homogenous catalyst: exists in teh physical state that is the same as teh reaction it catalyzes (ex: aqeous solution and aqeous solution)

Front 11

rate law for a one step reaction

Back 11

Rate=k[A]

Front 12

general rate law for more-than-one step reaction

Back 12

rate=k[A]^m[b}^n

Front 13

method of intial rates

Back 13

determines reaction order by comparing the initial rates of a reaction carried out w/ varying reactant concentrations

Front 14

instantaneous rate

Back 14

rate of decomposition at a specific time

(find the general rate law and multiply it out)

Front 15

complex reaction

Back 15

one that consists of 2 or more elementary steps

Front 16

reaction mechanism

Back 16

the complete sequence of elementary steps that make up a complex reaction

Front 17

intermediate

Back 17

a substance produced in one elementary step and consumed in a subsequent elementary step.

-do not appear in net chemical equation

Front 18

rate-determining step

Back 18

the slowest of the elementary steps in a complex reaciton.

Front 19

acidic solution

Back 19

-contains more H+ ions than OH- ions

Front 20

basic solution

Back 20

contained more OH- ions than H+ ions.

Front 21

neutral solution

Back 21

contains equal amount of H+ and OH- ions

Front 22

Arrhenius model

Back 22

an acid is a substance that contains hydrogen and ionizes to produce hydrogen ions in aqueous solution
-base is a substance that contains a hydroxide group and dissociates to produce a hydroxide ion in aqueous solution.

es: HCL > H+ + Cl-
ex: NaOH > Na+ + OH=

Front 23

Bronsted-Lowry model

Back 23

an acid is a hydrogen-ion donor and a base is a hydrogen-ion accetor.

Front 24

conjugate acid

Back 24

the species produced when a base accepts a hydrogen ion from teh acid.

Front 25

conugate base

Back 25

species that results when an acid donates a hydrogen ion to a base.

Front 26

conugate acid-base pair

Back 26

consists of two substances related to eachother by the donating and accepting of a single hydrogen atom

Front 27

amphoteric

Back 27

the term used to name substances such as water that can be both an acid and a base

Front 28

strong acid/weak acid

Back 28

acids that ionize completely/an acid that ionizes only partially in dilute aqueous solution

-weak acids produce fewer ions and thus cannot conduct electricity as efficiently as strong acids.

Front 29

if an acid is strong..its conjugate base is ____

Back 29

weak

Front 30

acid ionization constant

Back 30

the value of the equilibrium constant expression for the ionization of a weak acid.

Front 31

strong base

Back 31

dissociates entirely into metal ions an dhydroxide ions

(metallic hydroxides are strong bases)

Front 32

weak base

Back 32

ionizes only partially in dilute aqueous solution to form teh conjugate acid of the base and hydroxide ion.

Front 33

neutralization reaction

Back 33

a reaction in which an acid and a base react in aqueous solution to produce a salt and water

Front 34

salt

Back 34

-made up from cation from a base and a anion from an acid
-doubt-replacement reaction

Front 35

titration

Back 35

a method for determining the concentration of a solution by reacting a known volume of the solution with a solution of known concentration.

Front 36

equivalence point

Back 36

the stoichiometric point when teh OH equals the H

Front 37

salt hydrolysis

Back 37

the anions of the dissociated salt accept hydrogen ions from water or teh cations of the dissociated salt donate hydrogen ions to water

Front 38

redox reactions

Back 38

a reaction in which electrons are transferred from one atom to another

Front 39

oxidation

Back 39

the loss of electrons from atoms of a substance
-oxidation number goes up

Front 40

reduction

Back 40

the gain of electrons by atoms of a substance
-oxidation number is reduced

Front 41

oxidizing agent

Back 41

substance that oxidizes another substance by accepting its electrons (the substance that is reduced)

Front 42

reducing agent

Back 42

the substance that reduces antoher substance by losing electrons (the substance that is oxidized)

Front 43

oxidation-number method

Back 43

the total increase in oxidation numbers(oxidation) must equal the total decrease of oxidation numbers (reduction) of the atoms involved in the reation. this is the technique you use to balance it

Front 44

half reaction

Back 44

one of teh two parts of a redox reaction-oxidation half alone or reduction half alone

Front 45

covalent bond

Back 45

the chemical bond that results from teh sharing of valence electrons

Front 46

molecule

Back 46

formed when two or more atoms bond covalently

Front 47

Lewis Structures

Back 47

use electron-dot diagrams to show how electrons are arranged in molecules
ex: Hydrogen is represented by H:H or H-H

Front 48

sigma bonds

Back 48

single covalent bonds
-occurs when electronspair is shared in an area centered between two atoms.
-when two atoms share electrons, valence atomic orbital of one atom overlaps or merges w/ the valence atomic orbital of another atom

Front 49

pi bon

Back 49

formed when parallel orbitals overlap to share electrons

Front 50

oxyacid

Back 50

any acid that contains hydrogen and an oxyanion

Front 51

structural formula

Back 51

uses letter symbols and bonds to show relative positions of atoms

Front 52

resonance

Back 52

condition that occurs when more than one valid Lewis Structure can be written fora molecule or ion.

Front 53

coordinate covalent bond

Back 53

when an atom donates a pair of electrons to be shared with an atom or ion that needs two electrons to become stable

Front 54

VSEPR model

Back 54

model based on an arrangem,ent that minimizes the repulsion of shared and unshared pairs of electrons around the central atom.

Front 55

hybridization

Back 55

process in which atomic orbitals are mixed to form new, identical hybrid orbitals.polar covalent

Front 56

structural formula

Back 56

uses letter symbols and bonds to show relative positions of atoms

Front 57

resonance

Back 57

condition that occurs when more than one valid Lewis Structure can be written fora molecule or ion.

Front 58

coordinate covalent bond

Back 58

when an atom donates a pair of electrons to be shared with an atom or ion that needs two electrons to become stable

Front 59

VSEPR model

Back 59

model based on an arrangem,ent that minimizes the repulsion of shared and unshared pairs of electrons around the central atom.

Front 60

hybridization

Back 60

process in which atomic orbitals are mixed to form new, identical hybrid orbitals.

Front 61

polar covalent bond

Back 61

when there is unequal sharing of electrons
-large differences in electronegativeity