• 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...

Introduction

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.

Middle

-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.

Conclusion

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. Free essay

    Close Your Eyes

    Waiting for me to tell him what had actually happened. I suppose I could tell him, I could use some advice. "Alright then, I'll tell you" Immediately he stopped walking, turned round and sat down on the nearest sit. He's like a girl. Always up for a bit of gossip.

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

    Rate = ?[reactants] (where ? refers to the change) ?t The initial rate will be taken, therefore the gradient line will start at zero, and thus Y1 and X1 will equal 0. From this it can be shown that, Rate = Y2 - 0 X2 - 0 = Y2 X2 Therefore, for concentration 0.2 cm3: rate = 196 /

  1. Investigate various ways of increasing the rate of a chemical reaction and evaluate which ...

    reactants in solution * Temperature of reactants * The presence of light * The presence of a catalyst * The surface area of the solid reactant Yet how may one go about measuring the rate of a reaction? In the car, one may take readings of the distance that the

  2. Investigating Factors Affecting the Rate of a Chemical Reaction

    I have decided that I am going to alter the temperature by calculating the rate of reactions at intervals of 20,30,40,50,60,70 0C this should give me a varied set of results Measure 5cm3 of HCL using a measuring cylinder. Measure 50cm3 of 0.03moles/dm3 concentration of THIO also with a measuring cylinder.

  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. Investigating the Factors That Affect the Rate of a Chemical Reaction

    These key factors make successful collisions. There are factors that speed up the process of a reaction and slow them down. The key factors that will the rate of the chemical reaction are: * Temperature * Catalyst * Concentration * Surface area Temperature Increasing the temperature increases the rate of reaction, this is because when a

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

    Amount of the reactants It is important to keep the amount of reactants constant in the experiment because, as the reactant is used up, so the reaction slows down. This means a small amount of solid will have a different reaction time to a large amount.

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

    the table to make sure no-one falls � Never run in the lab � Always stand up when carrying out experiments so we can move away if we are in any danger Prediction I predict that the higher the concentration the faster the reaction will take place this is because

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