Rate of chemical reaction is how fast the ….
Reactants are changed into products
Slow reactions :
Rusting iron, chemical weathering (acid rain damage to limestone building)
Fast reactions :
Burning, explosions
Find speed of reaction by recording amount of ….. or …. over ….
Product formed
Reactant used up
Time
Steeper the line, the …..
Over time the line becomes less steep as …..
Faster the rate of reaction
The reactants are used up
Quickest reactions have the …. lines and become flat in the …. time
Steepest
Least
Rate of chemical reaction depends on:
- the …… of reacting particles - the more collisions there are, the ….. the reaction
- the …… during collision - particles must collide with …… for collision to be successful
Collision frequency
Faster
Energy transferred
Enough energy
Activation energy = …… - particles need this to ….
Minimum amount of energy that particles need to react
Break bonds in the reaction and start reaction
Increase rate of reaction by increasing ….
Number of collisions or amount of energy particles collide with
Rate of reaction depends on 4 things:
Temperature
Concentration of solution / pressure of gas
Surface area
Catalyst
Increase rate of reaction by (4x)
- increasing temp
- increasing concentration / pressure
- increase surface area
- use catalyst
INCREASING TEMP
- when temp increase, particles all …..
- which means they collide …..
- the faster the particles move, the more ….. - so more of the collisions will have ……
Move faster
More frequently
Energy they have
Enough energy to make reaction happen
INCREASING CONC. OR PRESSURE
- more concentrated = ….. knocking about in the … of solvent
- increased pressure = same number of …. in a … place
- makes collisions …..
More particles
Same volume
Particles
Smaller
More frequent
SURFACE AREA INCREASE
- if one reactant is solid, breaking it up to smaller pieces will increase it’s …..
- means that for …. volume of solid, particles have more ….., so more ……
Surface area to volume ratio
Same
Area to work on
Frequent collisions
CATALYST USE
- catalyst is a substance that …. without it …..
- all catalysts work by …. - they do this by providing an ….. with a ……
- enzymes are …… - they catalyse reactions in living things
Speeds up a reaction
Being used up in the reaction
Decreasing the activation energy needed for reaction to occur
Alternative reaction pathway
Lower activation energy
Biological catalysts
Reversible reactions are shown by
_________>
<————
As reactants react in reversible equation, their concentration ….. so ….. will ….. - but as more and more …. are made, the backwards reaction will …..
Fall
Forward reaction
Slow down
Products
Speed up
System at equilibrium =
Forward reaction same rate as background reaction - so no overall effect so concentrations of reactants and products won’t change
Equilibrium only reached if …..
Reversible reaction takes place in a closed system
If equilibrium lies to right, concentration of products is …… than that of the reactants
Greater
If equilibrium lies to left, the concentration of products is …. than that of the reactants
Lower
Position of equilibrium depends on : 3x
Temperature
Pressure (of gases)
Concentration of reactants and products
In reversible reactions one direction is ….. and the other is …..
Exothermic
Endothermic
In a reversible reaction, the energy transferred ……. is equal to the energy thransformed ….
From the surroundings by the endothermic reaction
To the surroundings by the exothermic reaction
