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

Analysis of Chlorine in Commercial Bleaching Solutions

Extracts from this document...

Introduction

Experiment 6 (28-11-08) Analysis of Chlorine in Commercial Bleaching Solutions Objective To determine the molarities of sodium chlorate (I) in two brands of bleach solution by titration. Theory Reaction between chlorate (I) and iodide ions with the present of sulphuric acid: CIO- (aq) + 2I- (aq) + 2H+ (aq) � Cl- (aq) + I2 (aq) + H2O(l) Reaction between hypochlorite ions and iodine: 2S2O32- (aq) + I2 (aq) � 2I- (aq) + S4O62- (aq) Procedures a. Determine the total volume of bleach in the commercial bottles provided. b. Note the price of the sample. c. Wash a 25.0 cm3 pipette with distilled water and then with the bleach solution. d. Pipette 25.0 cm3 of the bleach into a 250.0 cm3 of volumetric flask. e. Make up to the graduated mark of the volumetric flask. f. Stopper the flask and invert it several times in order to mix the contents well. ...read more.

Middle

2840 600 Price ($) 20 7.20 Brand Name of bleach : Clorox vs 0.1M Na2S2O3 1 2 3 Final burette reading (cm3) 4.60 8.70 2.20 Initial burette reading (cm3) 43.60 47.60 40.90 Volume of Na2S2O3 added (cm3) 39.00 38.90 38.70 Mean volume = () / 3 = 38.87 cm3 Brand Name of bleach : Kao vs 0.1M Na2S2O3 1 2 3 Final burette reading (cm3) 10.00 1.40 25.30 Initial burette reading (cm3) 33.80 25.30 49.00 Volume of Na2S2O3 added (cm3) 23.80 23.90 23.70 Mean volume = () / 3 = 23.80 cm3 Calculations Clorox No. of mole of S2O32- = = 3.89 x 10-3 mol By equation, no of moles of S2O32- : I2 = 2 : 1 ? no. of moles of I2 liberated = = 1.944 x 10-3 mol By equation, no of moles of I2 : CIO- = 1 : 1 ? no. of moles of CIO- = 1.944 x 10-3 mol No. ...read more.

Conclusion

It loses its function. Suggestion for the improvement - Keep the bleach solution away from sunlight. - Start titration immediately after adding potassium iodide solution and sulphuric acid into the diluted bleach solution. - Starch solution should be freshly prepared before used. Question 1. Clorox is the 'best' buy as it is relatively cheaper than Kao for 1 mole of sodium chlorate (I), which is the basis of commercial bleaches. 2. Sulphuric acid is used to provide hydrogen ions for the reaction between chlorate (I) and iodide ions. 3. First, when bleaching solution is put under sunlight, CIO- ions may be decomposed into chloride ions and oxygen gas. 2CIO- (aq) � 2CI- (aq) + O2 (g) Second, bleaching solution may react with carbon dioxide in air. Chlorate (I) ions in bleaching solution can react with carbon dioxide in air to form carbonate, water and chlorine gas. 2ClO-(aq) + CO2(g) � CO32-(aq) + H2O(l) + Cl2(g) Practical Report (Experiment 6) F.6A Angel Chan (4) Page 1 of 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 Classics 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 Classics essays

  1. To determine the indicator range of some acid-base indicators

    The principle behind the color change of indicator mainly lies on the ratio between the indicator and its conjugate counterparts which had different color. The indicator was a weak acid or a weak base itself which dissociated in water to set up an ionic equilibrium.

  2. Odysseus: Critical analysis

    The long-enduring Odysseus must now set out for home" . Calypso, following the custom of hospitality, welcomes Hermes and offers him food and refreshments. She has no choice but to set Odysseus free and help him on his way.

  1. Determination of Chlorine and Iodine in Water

    The initial volume of the sodium thiosulfate was measured from the buret and then the final volume was taken after the sodium thiosulfate was added to the KIO3 solution. These were subtracted from one another to get the volume of the amount released into the KIO3 solution.

  2. Arden vs. Freddy - Creative writing.

    Bosh inbounded the ball and somehow it gotten into Arden's hand. Launching his mind straight Freddy was determined not to let Arden score anymore. Arden tried to get by Freddy but it wouldn't work, his defense was great at the moment, Lebron like Arden tried again using a different crossover but also again nothing.

  1. What was the function of hadrians wall

    The last idea is most unlikely, the ditches would have most likely have drained water from their surrounding and there is no evidence of any drainage or paving at the bottom of the ditch and therefore they would have had more of a swap in the bottom of it making running or marching nearly impossible.

  2. An Analysis of The Simpsons.

    They say 'Call this a soccer riot' and bring out weapons. These fans are conforming to the stereotype of Scottish people and British hooligans. This stereotype has been exaggerated so that it can be brought to our attention and so we realize how silly the stereotype is.

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