Rate of reaction is a measure of how quickly a reaction occurs - what is measured is the change in amount of either reactant or product per second.
Rate of reaction is explained by collision theory. Reactants must collide with enough energy before they will react. Collisions with enough energy are known as "successful collsions". The more successful collisions per second, the faster the rate.
Explain how the four main factors affect rate of reaction.
You will need to: state what each factor is; say how if affects rate; and explain how this happens.
Post your answer in the comments section.
Katie McFarlane;
ReplyDeleteThe four main factors that effect the rate of
reation are the temperature, amount of catalyst, the concentration and the surface area of the reactant.
The temperature increases the rate of reation because the the particles move faster when hot and if the particles are moving faster, they collide with more energy to speed up the reaction.
The use of a catalyst effects the rate of reactiob as it is a substance which speeds up a reaction without being changed or used in the reaction, it gives reacting particles a surface to stick to where they can bump into eachother, increasing the number of successful collisons.
The concentration effects the rate of reaction because if a solution is more concentrated it means there are reactant particles in the same volume of solvent.
And lastly a cange in surface area effects the rate of reation. If you the solid particle is in a large 'Lump' then its reacion time takes longer but is the reactant is in smaller pieces it will have a larger surface area, this means the particles around it have more area to work on so the there will be more collisions.
David Treen
ReplyDeleteThe four main factors which affect the rate of reaction are the temperature, concentration, pressure of reacting gases and the surface area of reacting solids. These all can influence the reaction in different ways.
Temperature: Temperature affects the reaction by, in most cases, speeding it up. This is because there is more energy given to the molecules (as heat) so therefore speeding up their 'collisions' and ultimately, speeding up the reaction itself.
Concentration: Concentration can affect the rate of reaction in two different ways, it can either speed it up or slow it right down, this depends on the levels of concentration. For example, if we re-do the experiment with the marble chips and acid, a higher concentration of acid would speed up the reaction as there is more acid to break down and react with the marble. On the other hand, a lower concentration of acid would slow it down as the smaller amount of acid would still have the same sized marble to break down and react with.
Pressure of reacting gases: The pressure of reacting gases influences the reaction similarly to the concentration, if the pressure is higher then it will speed it up but if the pressure is lower then it will slow it down. The pressure of the reacting gases, when increased, helps speed up the rate of reaction as there is more particles but in the same volume. This increased number of particles increases the chance of collisions occuring and the reaction happening quicker. Its the opposite to this for a lower pressure as there is less particles to collide and therefore makes the reaction happen, but at a slower speed.
Surface Area of reacting solids: The surface area of reacting solids also works similarly to the pressure and concentration in the sense that if you increase the surface area, the speed of reaction will increase too. This increase in the rate of reaction is because when we increase the surface area of a reacting solid, we are exposing more particles to the other reactant, this then increases the chance of collisions happening which results in a quicker rate of reaction.
There are 4 main factors that affect the rate of reactions. They are:
ReplyDelete- Temperature
- Concentration and Pressure
- Its Physical State
- Catalyst
The temperature affects the rate of reaction. If it is increased then the rate of reaction is also increased. If the particles are given more energy, they will move about more quicker and the chance of a collision will be higher. A collision usually ends up with a reaction.
The concentration and pressure also affects the rate of reaction. If the pressure of a reacting gas or the concentration of a reactant is increased then the rate of reaction will also be increased. If there are more reactant particles that have the same volume then there is a greater chance that they will collide and react.
The physical state of a reactant also affects the reaction rate. If a solid reactant is ground into a powder or made into smaller pieces then the rate of reaction increases. As its surface area is increases then the particles are exposed to other reactants. This means there is a larger chance of them reacting.
A catalyst also affects the rate of reaction. It can speed up the rate of reaction without being used up. Catalysts do this by lowering the activation energy needed.
The four main factors are :
ReplyDeleteTemperature- An increase or decrease in temperature can change the way a reaction happens because some things react better in different temperature conditions to others. If something would react better in a hotter temperature and it is made to react it something cold then the reaction time will be larger as the raction will take more time to happen.
Concentration and pressure- IF a chemical is more concentrate then there will be more oarticles meaning that the particles will collide more and the reaction will therefore happen more quickly.
Physical state- Things such as liquid and gas can mix together easily so the particles collide quickly making the reaction quicker. If there is a solid in the mixture then the reaction has to take place on the solid.
Catalyst- They provide an alternative route for the chemical reaction meaning the particles have the enery to collide quickly.
Temperature: If the temperature is increased, so is the rate of reaction. This happens because, if the temperature is increased, there is more energy in the collisions meaning more collisions will have activation energy resulting in the rate of reaction increasing.
ReplyDeleteCatalyst: A catalyst is a chemical that speeds up the rate of reaction, but isn't used up in the chemical changes. A catalyst makes it easier for the reactants to collide and decreases the activation energy needed.
Concentration of dissolved reactant: There is more particles so there is more successful collisions. This means rate of reaction speeds up.
Solid reactants are broken down: If it is broken down, the surface area is increased meaning more particles are exposed to the other particles and there is a greater chance of particles colliding. This again increases the rate of reaction.
Ian Kelly:
ReplyDeleteTemperature - An increase or decrease in temperature means fewer or more particles will have the required energy.
Concentration and pressure - If the concentration or pressure of a chemical increases, there will be more particles within a space, particles with therefore collide more often.
Physical state - If particles are in the same phase, then it is very easy for them to mix with each other
Catalyst - A catalyst works by changing the energy pathway for a chemical reaction
Temperature- Certain things react faster/slower at different temperatures.
ReplyDeleteConcentration- The higher the concentration, the quicker the rate of reaction.
Surface Area- Increasing the surface area increases the rate of reaction.
Catalysts- These speed up the rate of reaction by increasing the frequency of collisions between particles.
Temperature: the higher the temperature the quicker the rate of reaction, this happens because there is more connect energy making the particles collide more frequently and faster.
ReplyDeleteConcentration: The higher the concentration the more particles there will be to make the reaction quicker, if there is more particles then they will collide more often where as a dilute mixture won't have as many particles so it would be slower
Volume: The higher the volume of particles there more particles there will be for a reaction to take place if there is a lower volume it will take a shorter amount of time because there isnt as many particles to collide.
Catalyst: A catalyst quickens the rate of reaction it makes the particles collide into eachother quicker without creating a compound.
one of the main factors that affect the rate of reaction is changing concentration or pressure.
ReplyDeleteIf the concentration of a dissolved reactant is increased, or the pressure of a reacting gas is increased then there are more reactant particles in the same volume. there is also greater chance of the particles colliding therefore the rate of reaction increases. another factor is changing particle size. If a solid reactant is broken into small pieces or ground into a powder the surface area is increased so more particles are exposed to the other reactant and there is a greater chance of the particles colliding. another factor is change in temperature, if you increase the temperature then the particles move quicker making it more likely for them to collide causing a faster reaction. catalysts also affect the rate of reaction. With a catalyst there are more collisions in a reaction, so the rate of reaction increases. although different reactions need different catalysts.
-eve.
Laura Hobden
ReplyDeletetemperature- speeds up the rate of reaction if higher by making the particles move quickly, therefore increasing the chance of collision. If it is at a low temperature then the particles would move slower therefore slowing the rate of reaction down as it would take longer for the particles to collide
concentration- a higher concentration will speed up the rate of reaction because the higher the amount of reactant particles the higher the chance of the particles colliding
surface area- speeds up the rate of reaction because the more of the particle exposed to another particle the higher the chance they will collide, however if the surface area is smaller it will decrease the rate of reaction by exposing less of the particle to surrounding particles making it harder for them to collide
use of catalysts- speeds up the rate of reaction by lowering the activation energy needed, which means collisions would happen more frequently
The rate of reaction is affected by, the temprature the surface area of reactiants and the concentration and pressure of the reactiants.
ReplyDelete