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

Determining the of the Effect of the Concentration of Na2S2O3 on the Rate of Reaction

Extracts from this document...


Determining the of the Effect of the Concentration of Na2S2O3 on the Rate of Reaction In this experiment we reacted different concentrations of Na2S2O3 (aq) with a constant volume of HCl, and measured the time it took for the X drawn under the beaker in black marker to disappear. The equation for this reaction is: Na2S2O3 + 2 HCl → 2 NaCl + S + SO2 + H2O The concentration of the Na2S2O3 used in the making of these solutions is 0.2M. For Trial 1 and Trial 2 these are the measurements of the volumes of each solution: Solution Volume of Na2S2O3 (aq) (cm³)(±0.1) Volume of H2O (l) (cm³) (±0.1) Total Volume of Na2S2O3 (aq) and H2O (cm³)(±0.2) Volume of HCl (cm³) (±0.2) 1 10.0 40.0 50.0 5.0 2 20.0 30.0 50.0 5.0 3 30.0 20.0 50.0 5.0 4 40.0 10.0 50.0 5.0 5 50.0 0.0 50.0 5.0 These are the results for the time taken with each concentration for both Trials: Solution Time for Trial 1 (±0.4)(s) Time for Trial 2 (±0.4)(s) 1 125.2 133.2 2 61.4 65.1 3 40.0 36.7 4 29.1 29.8 5 24.1 23.4 Uncertainty Details: 1. The uncertainty in the volume of Na2S2O3 (aq) and H2O (l) is given by manufacturer of the burettes. As we find the change in the volume in the burette, the uncertainties are added, and the uncertainty in the volume is ±0.1cm³ 2. ...read more.


all experiments, so even though we do not know the change in concentration of each reaction, we know that it is about the same. Therefore if we plot 1/time against concentration, we should be able to see the relation between the concentration and the rate, even though we do not have the correct rate. Concentration of Na2S2O3 (aq) (M) Uncertainty in Concentration (M) 1/time (Rate) (mol dm-3 s-1) Uncertainty in Rate (mol dm-3 s-1) 0.0400 ±0.0006 0.00774 ±0.00002 0.0800 ±0.0007 0.0158 ±0.0001 0.1200 ±0.0009 0.0260 ±0.0003 0.160 ±0.001 0.0339 ±0.0005 0.2 Unavailable (0) 0.0420 ±0.0007 Now we can plot this: - As we can see in this graph, it is linear, and Rate is proportional to 1/time. This means that the order of the reaction with relation to Na2S2O3 is 1. Also as the gradient of the line is 0.2166, this tells us that in the rate equation K = 0.2166mol-1dm3s-1. So the rate equation is: Rate = 0.2166[Na2S2O3][HCl]y. However we do not know the order of HCl as we did not vary the volume of HCl. Conclusion To conclude, we have calculated the order of the reaction with respect to Na2S2O3 to be 1. This was efficiently experimentally calculated as shown by the graph above. The graph is very fitting, and there are no anomalous points on it. ...read more.


The temperature could have been monitored during each trial so we can see when the rate could have been affected by a rise/fall in temperature. Also if the room was air-conditioned at a constant temperature, this would have meant the room temperature would stay the same (assuming no windows/doors are opened in the time). The uncertainty in the stop watch was much smaller than the actual uncertainty, so I attempted to find my reaction time, which was 0.4. However, when conducting the experiment it is impossible to tell if every time my reaction time was that, as it may have been more or less. This may have increased or decreased the uncertainty here. I could have taken a larger range of samples for my reaction time to get a more accurate value. As I poured the HCl and started the stop watch at the same time, this meant there was a small delay between when I poured the HCl in and when the stop watch was started. This means that the time was a little bit less than it had to be, once again adding to the slight systematic error. I could have gotten a fellow class mate to press the stop watch as soon as I poured the HCl in, so that there was a much small delay, and more precise results, as well as a smaller systematic error. ________________ [1] Information from http://en.wikipedia.org/wiki/Light_meter Last accessed 02/26/2013 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate 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 International Baccalaureate Chemistry essays

  1. Investigate the rate of reaction of luminol in various factors. The objective was to ...

    is 10 times smaller than that of 0.3M, which means in each seconds, there are 10 times less of luminol molecules being oxidized. I expect the time for chemiluminescence would be shorter for 0.3M and longer for 0.03M, and more light would be produced for 0.3M.

  2. Chemistry extended essay - investigate the effect of 2-bromo-2-methyl propane concentration and temperature of ...

    hydrogen - bonding, 2- Cations are solvated by nucleophilic sites on water molecule (oxygen). And in this case of t-butyl carbonium ion the nucleophiles form strong covalent bond to carbon and converting the intermediate to a substitution product. The reaction mechanism is a sequential account of each transition state and

  1. Using Solubility Rules to Indentify Unknown Solutions

    = 5% Moles of solute Concentration ( M) = 0.1M = ? x = 0.0002 1% x= 0.0002 2x10-5 g Mass of solute Moles = 2x10 -4 1% = ? x = 2x10 -4 x 58.4 x = 0.1 0.00002g x = 0.1 2x10 -5 Precipitate equation E = XY + PS = XY(aq)+PS(aq)

  2. Group 4

    For simplicity, in the discussion below, we will consider only the case of a driver hitting the steering wheel. If there is a restraining device as an airbag, the force of impact decreases, hence, the airbag reduces the rate of deceleration.

  1. How duration affects the rate of electrolysis in a Voltaic Cell

    (Different time intervals would result in a different mass change) This can be calculated simply by doing the following: Mass change = final mass - initial mass Due note however that this formula can only be used for calculating the mass change taking place at the cathode (copper electrode where reduction takes place).

  2. Investigating the Effects of Surface Area on the Rate of Reaction

    Therefore I would like to state a few things I would like to alter, if ever I got the change to do this experiment again. 1. Apparatus 1. Next time, instead of using a stopwatch, I would like to

  1. Measuring the fatty acid percentage of the reused sunflower oil after numerous times of ...

    And my hypothesis is that after many 25 frying the sunflower oil which is used to fry the potatoes will have an increase in its free fatty acid percentation as a harmful effect. KEY VARIABLES: Independent Variable: Amount of frying (5, 10, 15, 20, 25 times)

  2. Reaction Rate

    This will indicate the rate at which each concentration reacts and allow us to draw conclusions on how altering the concentration affects the rate of reaction between an acid solution and metal substance. We will measure this variable through the application of a stopwatch and gather recordings/data in seconds.

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