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

Determine the concentration of a limewater solution.

Extracts from this document...


Name: Aisha Trew Candidate Number: 6535 Centre Name: Bullers Wood school Centre Number: 14217 To determine the concentration of a limewater solution Aim: To do an acid based titration to find out the concentration of limewater Introduction In this experiment, an acid-alkali titration will be done between calcium hydroxide and hydrochloric acid to find out the exact concentration of calcium hydroxide. Acid + alkali � salt + water Hydrochloric acid + calcium hydroxide � calcium chloride + water Symbol equation 2HCl(aq) + Ca(OH)2(aq)� CaCl2(aq) + 2H2O(l) I'll be using phenolphthalein indicator because it is good with strong acid and alkalis, it will be added to the hydrochloric acid which will turn the solution pink/red, when the solution is neutralise, therefore the end of the titration the solution will then turn clear. The concentration of the hydrochloric acid given is 2.00 mol dm-3 which is too concentrated to titrate the calcium hydroxide. To find the concentration needed to neutralise the calcium hydroxide which concentration is approximately 1 g dm-3. ...read more.


* Fill the concentrated hydrochloric acid in the graduated syringe up to 2.5 cm3. * Put the hydrochloric acid from the graduated syringe into a 250cm3 beaker, and add diluted water until the 250cm3 mark and stir with a glass rod. * Then pour into a 250cm3 volumetric flask and fill until 250cm3 mask accurately, this is done by filling up until the bottom of the meniscus measures from the eye level. * Get the 250cm3 of calcium hydroxide from a beaker use a 25cm3 pipette and put it into a conical flask * Place the conical flask on top of a tile * Set up the clamp and stand to hold a burette * Fill the burette with the diluted hydrochloric acid making sure the bottom of the burette is filled with hydrochloric acid. * Put the burette on the clamp, and record the starting point of the acid * Add a few drops of phenolphthalein indicator into the calcium hydroxide and it will turn the solution pink/red * Put the conical flask underneath ...read more.


The moles used per titration = volume x concentration = 0.02 x (31.8/1000) = 0.000636 mol As the chemical equation is: [2HCl(aq) + Ca(OH)2(aq) � CaCl2(aq) + 2H2O(l)] Ratio of HCl and Ca(OH)2 is 2:1 Therefore moles of calcium hydroxide: 0.000636 /2 = 0.000318 Concentration of Ca(OH)2 = moles/volume = 0.00318/(25/1000) = 0.01272 mol dm-3 Concentration of Ca(OH)2 in g dm-3 = concentration x mr = 0.01272 x (40.1+(16 x 2) +2) =0.01272 x 74.1 = 0.94 g dm-3 (2.d.p) Evaluation At the beginning of the experiment, you were told that the limewater given to you was just approximately 1 g dm-3. The answer calculated is 0.94 g dm-3, which is only 0.06 away from the approximated amount. The average concentration found of the limewater solution is 0.76 g dm-3. My results were 0.18 g dm-3 more concentrated than the average. This could be because the titration method as it is difficult to get the exact volume of hydrochloric acid needed to neutralise the calcium hydroxide solution that is why everyone final concentration for calcium hydroxide was slightly different. ...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. Find the concentration of limewater solution Titration

    Repeat this last procedure 3 times. Method of Titration Apparatus * 0.02M HCl * 250cm� of Ca(OH)2 * Beaker x2 * A conical flask * White tile * A tray * Methyl orange * Non-permanent marker * A 5cm� pipette * A 25cm� pipette * A pipette filler * A burette * Funnel * A clamp

  2. Determine the solubility of calcium Hydroxide solution with the aid of the titration process

    It is a very reactive acid and will provide us with visible conclusions of the experiment. Calcium Hydroxide Will be contained in a glass beaker and placed under the burette containing the acid.

  1. I have to plan an experiment to find the solubility of calcium hydroxide, Ca(OH)2, ...

    Once the initial volume is recorded, open the tap of the burette and allow the acid to pass into the conical flask slowly. Make sure it is done slowly otherwise the neutralisation may happen to quickly before you can close the tap.

  2. To determine the concentration of limewater solution

    shaking the conical flask to get an accurate result off the level on the burette. Safety Before any of the experiments are carried out, these safety points must be read. * Must wear safety goggles when near any chemicals. * HCl is in a high concentration so gloves must be worn when using it.

  1. determining the concentration of a limewater solution

    Caution should also be taken when handling hydrochloric acid, not to inhale deeply. Factors that should be taken into account: There are also certain factors that should be accounted for during the procedure. It is important to keep the temperature of the surroundings steady, and as close to the ideal room temperature (21�C)

  2. The aim of this experiment is to determine as accurately as possible the concentration ...

    pipette to ensure all remaining Hydrochloric acid is removed from the pipette. Because I used a pipette to measure out the Hydrochloric acid, I will need to wash it out with distilled water. I am going to collect these washing because there may be some Hydrochloric acid traces in the pipette.

  1. To determine the concentration of Limewater solution

    I will calculate this later on. Also it is very important to find out which indicator to use as certain chemicals require certain indicators. Preliminary work show how screened methyl orange should be used. However what is the difference methyl orange and screened methyl orange?

  2. To determine the concentration of a limewater solution

    Afterwards this solution needs to be shaken 35 times to ensure a uniform solution and this can be done by placing a bung securely on the conical flask. This leaves me with 200cm3 of 0.02 mol-dm-3, which is a lot more suited to the titration.

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