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

Determination of the purity of Sodium Carbonate

Extracts from this document...


Determination of the purity of Sodium Carbonate Aim: To determine the percentage purity of a sample of sodium carbonate. Equation: Na2CO3 + 2HCl --> 2NaCl + H20 + CO2 Sodium Hydrochloric Sodium Water Carbon Carbonate Acid Chloride Dioxide Chemicals: * 4.00 g dm-3 of impure Sodium Carbonate in solution * 1.00 mol dm-3 Hydrochloric acid Apparatus: * 50cm3 burette burette clamp and stand * 25cm3 bulb pipette pipette pump * Teat pipette * Conical flask white tile * 250cm3 graduated flask * 1 beaker for waste funnel * Methyl Orange indicator * Distilled water Method: To determine the percentage purity of a sample of impure sodium carbonate we must first find out how much, in volume, hydrochloric acid it takes to neutralise the solution (this is an acid and base titration and will need an indicator). To do this I will need to adhere to the following method; 1. Clamp the burette carefully. Fill the burette with the hydrochloric acid using the funnel. Remove the air space below the tap and use the wastage beaker to catch any of the acid. ...read more.


I should use a burette to add an accurate volume of hydrochloric acid to the graduated flask, and when filling up the flask a teat pipette should be used when making up the final few cm3 of the solution. Risk analysis: There is little risk involved in this experiment as all the solutions used are very dilute and are unlikely to harm anyone if spilled. However, for safety measures, a lab-coat and goggles should be worn and extra care should be taken when using the glassware. Error Analysis: The following table shows the error that can occur when reading off the measuring device. I must take these into consideration for my experiment as it could affect my results. Volume / cm3 Error / cm3 Error per cent / % Graduated flask 250 � 0.20 0.08 Bulb pipette 25 � 0.06 0.24 Burette 20 � 0.10 0.50 Pipette 2.5 � 0.04 0.16 The error taken for the burette is as such because I am taking a reading from it twice (initial and final reading), but I am reading to the nearest 0.05cm3 to give a greater degree of accuracy. ...read more.


From the average titration volume I will be able to calculate the percentage purity of the sodium carbonate solution. Moles HCl = Average HCl used x concentration HCl 1000 = 16.65 x 0.08 1000 = 0.00132 Moles Na2CO3 = moles HCl 2 = 0.00066 Moles Na2CO3 = Volume x Concentration 1000 Concentration Na2CO3= Moles Na2CO3 x1000 Volume = 0.00066 x 1000 250 Percentage purity of = Concentration Na2CO3 x RFM Na2CO3 = 0.0264x 106 = 0.27984 Moles HCl = 16.65x 0.08 1000 ? Moles Na2CO3 = 16.65 x 0.08 in 25cm3 1000 x 2 ? Moles in 250 cm3 = 16.65 x 0.08 x 10 1000 x 2 ? Mass Na2CO3 = 16.65 x 0.08 x 10 x 106 in 250 cm3 1000 x 2 = 0.70596 ?Percentage purity = 70.596% of Na2CO3 I now need to take into account the errors that could have been made. Overall percentage = 0.50 + 0.24 +0.08 + 0.16 + 0.60 = 1.58% error So there is a possible error in my percentage purity of 1.58%, Possible percentage = 70.596 ? 1.58 x 100 purity of Na2CO3 70.596 with error = 73.2% to 68.4% Therefore the percentage purity of the sodium carbonate solution could range from the upper bound of 73.2%, to the lower bound of 68.4%. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Inorganic 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 AS and A Level Inorganic Chemistry essays

  1. Peer reviewed

    Determining the concentration of acid in a given solution

    5 star(s)

    needed to reach the rough end point * Fill up the burette again so that there is plenty of solution for the next titre * Read the value to the nearest 0.05cm3 and record it on the paper * Get a new conical flask and rinse it to ensure it

  2. Peer reviewed

    Deducing the quantity of acid in a solution

    5 star(s)

    It is the "open and close". This instrument will allow us to dispense very accurate the H2SO4 solution into the flask with the reagent, in this case, Na2CO3 with the indicator methyl orange. Burettes are extremely precise and are accurate to �0.05 ml.12 * Pipette and filler This type of

  1. effects Concentration and Temperature on the Rate of Reaction

    This in turn means that the rate equation so far looks like this: Rate = k[BrO3][Br -] Results With Respect to Sulphuric Acid The table below shows my results when varying the concentration of sulphuric acid: Concentration of Sulphuric Acid (mol/dm-3) Time Take For the Mixture to Turn Colourless (seconds)

  2. Chem Lab report. Standardization of hydrochloric acid by sodium carbonate solution

    the beginning was anhydrous because if it is hydrated, water in it will affect the mass of solid. Thus, the actual number of moles in the sodium carbonate solution will not be accurate and so the final result would be in great error.

  1. Lab report Determination of Enthalpy Change of Neutralization

    Q.5: H+ (aq) + OH- (aq) � H2O (l) Q.6: By the detailed calculation in the Result and Calculation section, the enthalpy change of neutralization is -54.8KJ mol-1 Q7: H+ (aq) + OH- (aq) � H2O (l) Q8: By the detailed calculations in the result and calculation section, the enthalpy

  2. Finding Out how much Acid there is in a Solution

    in eye: flood eye with water for at least 10 minutes, seek medical advice * Sulphuric Acid (H2SO4) o Corrosive at higher concentrations, but irritant if below 0.5 mol dm-3 o Spilt in laboratory: wash area with water o Spilt on skin: rinse affected area with plentiful water o Spilt

  1. Chemistry - Data Analysis

    polystyrene 0 90 90 90 90 90 90 90 90 90 0 90 90 90 2 79 79 80 82 81 82 82 82 83 2 79 82 82 4 72 72 73 76 76 76 75 76 77 4 72 76 76 6 67 67 68 70 69 71

  2. The aim of the courework is to find the unknow concentration of HCl

    5. after this stir using a glass rod to dissolve it completely 6. lastly transfer the solution in to volumaetric flask using the funnel. Remember pour down the glass rod Remove the last drop of solution from the glass rod on to the funnel.

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