Unit 9 Test

Question 1

The change in the amount of reactant or product per unit of time, generally calculated and expressed in M/sec
rate= change in [ ]/change in t

Answer 1

reaction rate

Question 2

atoms, ions, and molecules can react to form products when they collide, provided that the particles have enough kinetic energy and the correct orientation. kinetic energy you need=activation energy

Answer 2

collision theory

Question 3

a substance that increases the rate of reaction by lowering the activation-energy barrier; the catalyst is not used up in the reaction.

Answer 3

catalyst

Question 4

proteins that act as biological catalysts

Answer 4

enzyme

Question 5

a substance that interferes with the action of a catalyst and slows down the reaction rate

Answer 5

inhibitor

Question 6

a diagram that illustrates the potential energy of the reactants and products for a chemical reaction and how this energy changes during the reaction

Answer 6

potential energy diagram

Question 7

the minimum energy colliding particles must have in order to react

Answer 7

activation energy (Ea)

Question 8

An unstable arrangement of atoms that exist momentarily at the peak of the activation-energy barrier; is an intermediate or transitional structure formed during the course of a reaction.

Answer 8

activated complex (transition state)

Question 9

The amount of heart, or energy, absorbed or released in a chemical reaction; if change in H is positive then the reaction is endothermic, if change in H is negative then the reaction is exothermic

Answer 9

enthalpy (heat) of reaction (change in H)

Question 10

A reaction in which energy is absorbed from the surroundings

Answer 10

endothermic

Question 11

a reaction the releases energy to the surroundings

Answer 11

exothermic

Question 12

a reaction in which the conversion of reactants to products and the conversion of products into reactants occur simultaneously

Answer 12

reversible reaction

Question 13

a state of balance in which forward and reverse reactions are taking place at the same rate; no net change in the amounts of reactants and products occurs in the chemical system. rate forward=rate reverse

Answer 13

chemical equilibrium

Question 14

the relative concentrations of reactants and products of a reaction that has reached equilibrium; indicated whether reactants or products are favored in the reversible reaction Keq greater than 1= products favored Keq less than 1=reactants favored

Answer 14

equilibrium position

Question 15

when a stress is applied to a system at equilibrium, the system changes to relieve the stress.

Answer 15

Le Chatlier’s principle

Question 16

an equation that includes heat as either a reactant or product

Answer 16

thermochemical equation

Question 17

the ratio of product concentrations to reactant concentrations at equilibrium with each concentration raised to a power equal to the number of moles of that substance in the balanced chemical equation.

Answer 17

Equilibrium constant (Keq)

Question 18

What are the 4 factors that affect the rate of a reaction?

Answer 18

temp, concen, particle size, catalyst

Question 19

Tempurature affect

Answer 19

increases shifts away from side with heat
decrease shifts toward side with heat

Question 20

concentration effect

Answer 20

add reactant=right remove reactant=left
add product=left remove product=right

Question 21

catalyst effect

Answer 21

has no effect but has equal pull in reaction

Question 22

particle size effect

Answer 22

the smaller they are the more reactions can take place

Question 23

what does Keq tell use about reaction turning

Answer 23

Keq greater than 1 products favored
Keq less than 1 reactants favored

Question 24

Draw reaction diagram for exothermic and endothermic reactions

Question 25

Draw an energy diagram and solve for change in H and Ea and show the effect of a catalyst

Question 26

What is collision theory

Answer 26

a reaction needs to have the correct orientation and amount of energy for the reaction to actually happen temperature increase then number of collisions and energy of collision also increase.

Question 27

Whats a reversible ractin

Answer 27

when the change of reactants to products and change of products to reactants happens at the same time When the rate of forward and backward reactions are the same/ equal then its chemical equilibrium. the rate of a reaction depends on the frequency of collisions. the reactions don't stop but continue at the same rate so that the ratio of concentration reactants to products is equal. the concentration of reactants go down as the concentration of products increase until they even out.

Question 28

Concen Addition of reactant Addition of product Removal of a reactant removal of product Temp Increase decrease Press Increase Descrease

Answer 28

right left left right away from heat toward heat to less moles to more moles

Question 29

do number 10

Question 30

do 11

Question 31

do 12

Question 32

do 13

Question 33

N2O4 (g) reversible reaction 2NO2 (g) write equilibrium constant expression