Rates Of Reactions

Question 1

collision theory

Answer 1

chemical reactions occur because of collisions

collide, correct orientation, equal or greater amount of energy then activation energy

Question 2

Maxwell-Boltzmann distribution

Answer 2

reaction occurs because particles have greater energy or equal to Ea
therefore increase number of paritcles with surficent energy increases rate of reaction. because of increase frequency of successful collisions

Question 3

activation energy

Answer 3

minimum amount of energy required for a reaction to take place

Question 4

rate of reaction

Answer 4

measured by the change of concentration of a reactant per unit of time
speed of reaction

Question 5

factors that effect rate of reaction

Answer 5

1. change surface area of a solids particles. increase SA
2. concentration- increase number of particles in a given volume
3. pressure of gas- decrease the volume increase the pressure
4. temperature- increase allows for greater of proportion of particles to have equal or greater activation energy
5. catalyst- lowers activation energy allows greater amount of particles to have equal or great energy then Ea

• increases the frequency of collision- increase the proportion of successful collisions- increases the frequency of successful collisions, therefore, increasing rate of reaction

Question 6

catalyst

Answer 6

provides an alternative reaction pathway

lowers activation energy allows higher amount of particles to have the energy to collide

Question 7

Le Chatelier principle

Answer 7

systems at equilibrium partially opose every change that disrupts

if forwards in favored moves right
if reverse is favored moves left

Question 8

dynamic equilibrium

Answer 8

when rate of reaction of forward equals rate of reaction of reveres
concentrations of reactantts and products have not changed

Question 9

closed system

Answer 9

no exchange in matter

only exchange in energy

Question 10

endothermic reaction

Answer 10

absorbs heat from soroundings

products greater energy then reactants

Question 11

exothermic reaction

Answer 11

releases heat to soroundings

products less energy then reactants

Question 12

changing the equilibrium/ affecting it

Answer 12

1. increasing temperature favours endo/ decrease favours the exothermic
2. if reactant or product ( gas or solute) is added- concentration increases
   product added- favour reverse product taken- favours forward
   reactant added- favours forward reactant taken- favours reverse
3. increase preausre favours the way
   greater moles - less moles

eg- 2 moles —— 1 mole
favours forward

Question 13

haber proccess

Answer 13

industrial process to produce ammonium
reactants : hydrogen- from methane and steam + nitrogen - from air 1:3
products: ammonium

conditions- 400-450 degrees- surficent yield , 200 atm preasure- b/c cost effective
iron catalyst

yield 10-20 %

unreacted gasses reused