Rates Of Reaction 2 Flashcards
(26 cards)
Name 5 ways a reaction can be made to go faster
1- increased temperature 2- increased surface area 3- increased concentration 4- presence of a catalyst 5- increased pressure (if the reactants are gasses)
What 2 things does the rate of reaction depend on
1- the frequency of collisions between particles
2- he energy with which particles collide
What is the activation energy?
Is the minimum amount of energy needed for the particles to react is called the activation energy.
If you change the number of molecules that have the activation energy what will change?
The speed of the reaction
If particles collide with less energy than the activation energy what will happen?
They will not react, they will bounce off each other because there isnt enough energy to collide with
Why will increasing the surface are or a solid increase the rate of reaction?
Because it will allow more surface area for the particles to collide with and react
Why will increasing the temperature increase the rate of reaction
Because it will give them more kinetic energy, allowing them to have more energy to collide with
The particles will move faster, moving faster they will collide more frequently
Why does increasing the concentration increase the rate of reaction
Increasing the concentration pf one or more of the reactants will speed up because the molecules are more likely to collide. They have more to react with
What is a catalyst
Are substance ps that change the speed of a chemical reaction but is not used up during that reaction
Does a catalyst lower the activation energy
Yes
Is more product produced with a catalyst?
No they just produce the same amount of product more quickly
iron a catalyst in the production of?
Ammonia
Platinum is a catalyst in the catalytic…
Converters in a car exhaust
Why is catalysts important in industry? 2
- products can be made faster
- high temperatures are not needed which reduces costs in fuel and helps the environment
If a reversible reaction is exothermic in one direction what is it in the opposite?
Endothermic
What is equilibrium
When the forwards and backwards reactions are occurring at the same rate in a closed system
When is equilibrium reached?
When the forward and reverse reactions occur at exactly the same rate but the apparatus must prevent the escape of the reactants and the products. This is called a closed system
At equilibrium….. X2
1- the rate of the forward reaction equals the rate of the backward reaction
2- the concentrations of reactants and products do not change
If the concentration of reactants is GREATER than the concentration of products we say the equilibrium is on the…..
Left
If the concentration of the reactants is LESS than the concentration of the products the position of the equilibrium is on the
Right
During equilibrium how fast is the reaction
Initially, the forward reaction is fast but then it slows as the reactants are used up
Theoretical yeild=
Is the maximum possible yield from a chemical reaction
Actual yield=
Is the yield of product that you really get from carrying out a chemical reaction
Percentage yield
Is the percentage of product that you get compared to what is theoretically possible
