• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

An Investigation into the Factors which Influence the Rate of a Chemical Reaction.

Extracts from this document...


An Investigation into the Factors which Influence the Rate of a Chemical Reaction Aim The aim of this experiment is to find out what affects the rate at which a reaction occurs between sodium thiosulphate and hydrochloric acid. I want to find out whether and to what degree varying the concentration of sodium thiosulphate has any effect on the rate of reaction. Prediction I predict that the greater the concentration of Sodium Thiosulphate solution the faster the chemical reaction will take place. I think the concentration of a solution affects the rate of reaction because: 'The rate of reaction depends on how frequently the molecules of the reacting substances collide. A more concentrated substance has more molecules with a set volume than one which is more dilute one. This means because there are more molecules about, the frequency of collisions is greater and the reactions happen faster.' Method To find out what effect the concentration has on the rate of reaction, I will be measuring the time it takes for the reaction to complete when various different concentrations of sodium thiosulphate are used. ...read more.


-Size of Conical Flask This doesn't affect the rate of reaction, because it isn't included in the reaction itself. But it does affect our measurement of how long the reaction has taken to complete. If the conical flask is wider then the cloudiness will appear less concentrated because it will be spread across the larger area of the bottom of the conical flask, this will lead to it taking a longer time for the cross to disappear. -The Cross The cross could affect the results depending on how easily it can be seen. If it was very light, the measurement of how long the reaction took to make it disappear completely would be less, so this would mean the rate of reaction would seem faster. I can keep this constant by using the same laminated cross each time. -Movement of Reacting Mixture If the conical flask is shaken during the reaction then it may speed up making the rate of reaction quicker. Also if the mixture was to be stirred it would force the particles to collide more than they would have. As I have no way of keeping the stirring constant I will prevent any change from happening by not moving the mixture in any way. ...read more.


This makes collisions between the particles more likely. In a liquid increasing the concentration means having the reacting substance less dilute. The more water added means there are fewer molecules to react with as some have been replaced with that of water molecules. This is the factor I intend to change in my experiment. This should be easier to control than other methods of controlling reactions. Heat * The reason reactions happen slowly is because of an energy threshold below which a reaction will not take place. A certain amount of energy is required before the reaction will begin, this is called activation energy. This varies between different chemical reactions. A common way of speeding up reactions is to use heat, initially this makes the particles move quicker, giving them more kinetic energy, so more of them overcome the activation threshold, increasing the rate of reaction. Catalyst * Basically a catalyst is a substance which increases the speed of a reaction without being changed or used up in the reaction. Catalysts work by providing an alternative route for the reaction that has lower activation energy than that of the uncatalysed reaction. Because the activation energy along the catalysed route is smaller, more of the colliding molecules have the minimum energy needed to react, and so the rate of reaction is increased. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Patterns of Behaviour section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Patterns of Behaviour essays

  1. Investigating Factors Affecting the Rate of a Chemical Reaction

    I did outline in my plan that I was going to heat the Sodium Thiosulphate using a water bath, however, this option was not available to me due to the lack of time and resources, I ended up heating the Thiosulphate in a flask sitting on a gauze mat.

  2. Find out how the rate of hydrolysis of an organic halogen compound depends on ...

    If the substance has been indigested, do not induce vomiting. If swallowed, the mouth should be washed thoroughly with plenty of water and the patient should be given water to drink. Medical attention should be sought immediately. NOTE: Never give an unconscious person anything to drink.

  1. Free essay

    Close Your Eyes

    over and over again, babbling the same excuse about how Dougie had stolen it because he wanted to learn it. I smiled to myself. He looked so cute. This was amusing but I felt sorry for him. He genuinely thought I was annoyed. "Danny, Chill. I'm just messing with you.

  2. What factors effect the rate of a chemical reaction?

    acid � calcium chloride + water + carbon dioxide The chemical formula for this reaction is as follows: CaCO3(s) + 2HCl(aq)� CaCl2(aq) + H2O + CO2(g) I will collect the carbon dioxide as a measure of the rate of reaction.

  1. 'Investigating factors that affect the rate of chemical reactions.'

    This states that the rate of reaction simply depends on how often and how hard the reacting particles collide with each other. The basic idea is that particles have to collide with other in order to react, and they have to collide hard enough as well.

  2. An investigation into how concentration affects the rate of a chemical reaction.

    a collision should be doubled, as there is now twice the possibility of a collision-taking place initially. This can be thought of as like people in a refined space, if there are twice the number of people there will be twice the chance of people colliding.

  1. What factors effect the rate of a chemical reaction?

    Prediction: I can predict that there will be a positive correlation between the rate of the reaction and the temperature so that as the temperature is increased, the rate of reaction will increase Graph to show relationship between temperature and rate of reaction: The rate of reaction changes throughout, but

  2. What factors effect the rate of a chemical reaction.

    Therefore there are relatively more successful collisions and so the reaction rate increases. In order to ensure a fair test with reliable results, I will need to keep all variables constant apart from the one I am intending testing. The investigation I am going to investigate how a change in

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work