titration - I am to be given a sample of sulphuric acid thought to have a concentration between 0.05 and 0.15 mol dm- and have to find out the accurate concentration of the acid.

• In order to make a standard solution I will collect sodium carbonate with the mass that I had calculated by using a weighing boat, weighing scale and spatula.
• I will then place this in the 250cm³ volumetric flask and fill the volumetric flask with a small amount of distilled water, I will place the lid on the volumetric flask and then shake the flask so that the sodium carbonate dissolves into the distilled water.
• Once the sodium carbonate has dissolved in the volumetric flask I will then fill it up with distilled again but to the graduation mark using a wash bottle.

• I will then pipette 25cm³ of this sodium carbonate solution into a 250cm³ conical flask using a pipette and pipette filler and add 3 drops of the methyl orange indicator solution to the conical flask.
• After this I am going to rinse a burette with the sulphuric acid by filling it up and releasing its contents. After rinsing I will fill up the burette with the sulphuric acid and place it on the clamp and record its initial reading.
• I will then place the conical flask containing the sodium carbonate solution under the burette and then titrate it until the solution becomes clear.
• Once the solution has become clear I will record the burette’s final reading and take the initial reading away from it to find the titre.
• I will repeat the titration on a new sample of sodium carbonate another to time to ensure that I have reliable results and obtain and average.

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1. Bibliography

Below is the list of any sources I have used for my investigation.

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2. ANALYSIS

1. Results Table

From my results I have obtained two results that are consistent to ±0.2cm. These results are from the 2nd and 3rd trials. They are 37.60 and 37.50, in order for me to find out the concentration of the sulphuric acid used I will have to find the mean value of these values by adding the two values together and dividing by two. The average volume of sulphuric acid used is 37.55cm3.

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2. Calculations and Graph

After collecting a few consistent results I am now able to find the exact concentration of the sulphuric acid.

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3. Findings

From my results I have found that I have two anomalous results as a result of them being inconsistent. However, I did manage to obtain two consistent results. As a result of this I was eventually able to calculate the concentration of sulphuric acid used. The concentration of the acid was found to be 0.08 mol dm-3

3. EVALUATION

4. Suitability and Accuracy

I feel that my method was suitable for this investigation. This is because only a basic set up was required for my investigation. However, as with all investigations mine was not free from any flaws. There were plenty of flaws that had an impact on my results and as a consequence I do not have a decent set of results.

5. Percentage errors

For every trial I carried out there was slight errors. Below is a table showing the percentage errors.

The total percentage of errors can be found by adding the values in the last column together. The overall percentage of error in my investigation is ±41.58%. This is very significant as half the investigation seems flawed.

6. Significant Errors

In my investigation there were many significant errors within the procedure used and the measurements taken. I have listed the errors below.

Procedural Errors

• The amount of sulphuric acid placed into the sodium carbonate solution may have had fluctuations as the methyl orange can only be seen once you shake it and the flask was not shaken all the time.
• When I was making the sodium carbonate solution all the sodium carbonate may not have dissolved into the distilled water.

Measuring Errors

• The burette had an error of ±0.1cm³ which could have shown fluctuations in the amount of sulphuric acid that was used.
• The weighing scale had an error of ±0.005g which could have had an impact on the amount of sodium carbonate that was used for the experiment.

7. Improvements

I could have made many significant changes to my investigation to make it more reliable.

These include:

• Continuously shake the flask containing the sodium carbonate.