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

How the concentration of Sodium Thiosulphate affects the rate of reaction with Hydrochloric Acid.

Extracts from this document...


How the concentration of Sodium Thiosulphate affects the rate of reaction with Hydrochloric Acid Plan We will set up a conical flask on top a cross. We will vary the concentration of Sodium Thiosulphate by putting different amounts of Sodium Thiosulphate and water bye keeping the same total volume of 50cm�. We will then add 5cm� of hydrochloric acid. We will time how long it takes for the cross to completely disappear from site after the reaction has completely finished. Constants Variables Temperature Concentration of Sodium Thiosulphate Total amount of Sodium Thiosulphate + Water Size of conical flask Amount of hydrochloric acid Hydrochloric acid concentration Same person seeing when the cross disappears completely Experiment Prediction If the concentration of sodium Thiosulphate is change I predict that the rate of reaction will change. The higher concentration of Sodium Thiosulphate per cm� the quicker the reaction will take place. This is because the more Sodium Thiosulphate particles there are, the more chance, and the more successful collisions with Hydrogen+ ions in the Hydrochloric acid will be. I predict that if the concentration is doubled the rate of reaction will double. ...read more.


This means that when the concentration of Sodium Thiosulphate doubles, the reaction takes place twice as fast. This is because when the concentration doubles, the amount of Sodium Thiosulphate particles doubles, so collisions of Sodium Thiosulphate and Hydrochloric acid ions occurs twice as often. This means that the reaction is complete twice as quick, and the liquid will cloud up so we can't see the cross in half the time. For example when the volume of Sodium Thiosulphate was 20cm� and volume of water was 30cm�, the result for 1/time was 0.009s . And when the volume of Sodium Thiosulphate was 40cm� and volume of water 10cm�, the 1/time result was 0.018s . This is double the speed of half the concentration. Particle diagram: This shows that twice the amount of Sodium Thiosulphate particles there are the twice as likely they are to hit and react with a Hydrochloric acid ion to complete the reaction and make the cross disappear from site. Sodium Thiosulphate + Hydrochloric acid � Sodium Chloride + Sulphur + Sulphur dioxide + Water Na2S2O3 (aq) ...read more.


We may have been at different angles looking down on the cross through the solution which would mean that the cross may seem to disappear from one angle but may be still seen from another angle. To improve the reliability of the experiment we could put a light under the conical flask, instead of a cross. And use a light sensor attached to a computer program which would stop timing when the light had disappeared. The light would have to be quite dim otherwise it may shine through the liquid even when it had clouded up. It would also have to be done in the dark so that there is no interference from other light sources. We could improved the reliability of the experiment by using more accurate measuring equipment, such as a syringe to measure the liquids. We could extend our work further by using other acids besides Hydrochloric acid and note if there is any difference in time, if any. We could add a catalyst and vary the amount or size of the catalyst bits and not change the amounts of each solution. We could vary the temperature of the experiment by heating or cooling the Sodium Thiosulphate mixture and note the time for the same concentration. ...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 Aqueous Chemistry 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 Aqueous Chemistry essays

  1. Marked by a teacher

    Investigating The Rate Of Reaction Between Sodium Thiosulphate And Hydrochloric Acid

    4 star(s)

    I am going to Be careful not to get it onto my skin. Wash Hands - After the experiment I will wash my hands so that I have Washed any acid that I have touched when doing the experiment Wear Apron - I will wear a apron so that my

  2. Rate of reaction- Sodium Thiosulphate and Hydrochloric Acid.

    In my 1st and 3rd attempts I got 181 and 185. This means that the second attempt was probably incorrect. This could have been caused by any number of things such as: Measuring the actual measuring of the chemicals is difficult because of the meniscus of the liquid and the accurateness of the measuring cylinders.

  1. What factors affect the rate pf reaction between sodium thiosulphate and hydrochloric acid?

    Results Volume of Water in solution (ml) Volume of Sodium thiosulphate in solution (ml) Volume of Hydrochloric acid in solution (ml) Time taken for marker to disappear (minutes) 25 25 50 7:43 20 30 50 6:21 15 35 50 5:11 10 40 50 4:52 5 45 50 3:56 0 50 50 3:30 In order to get the

  2. to investigate how the concentration affects the rate of the reaction

    measuring the magnesium because I am relying on when the magnesium disappears and forms the new substance. During my experiment, I found out that if a large amount of magnesium reacted with a large amount of hydrochloric acid, the reaction will go over the top and the hydrogen produced cannot be recorded.

  1. The effects of concentration on reaction rate with sodium thiosulphate

    If I don't, then the readings from the stop clock would be wrong, and there would be a lot of anomalies. It is these anomalies that I should try to avoid. Safety precautions In this experiment, because I will be handling with liquids such as acids which is an irritant,

  2. Investigating what affects the rate of reaction between sodium thiosulphate and hydrochloric acid

    Lower pressure also lowers the rate of reaction. To control the pressure, the experiment will be executed in the same room. Amount The more acid, the more acid molecules there are to make meaningful collisions and react with the sodium thiosulphate.

  1. An Investigation on the Rate of Reaction between Sodium Thiosulphate and hydrochloric acid.

    I used distilled water every time, as normal tap water has chemicals in which could also change my results. I made the volume of water and thiosulphate the same each time.

  2. An investigation into whether sodium Thiosulphate concentration affects the rate of reaction.

    From my preliminary results I decided that it would be best to used 15cm� of acid because it reacted with the sodium thiosulphate. Also I realised that every time I had done an experiment, I would need to thoroughly clean out the test tube(s).

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