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

# Determining the Concentration of a Limewater Solution

Extracts from this document...

Introduction

Determining the Concentration of a Limewater Solution Introduction Previous to conducting my experiment, research was carried out and the results of it adapted to aid me in solving the problem set. In the Advanced Chemistry Student's Book by Nuffield, on page 86, I found a similar experiment to mine with a description of implementation, which aided me in the fact that I discovered the temperature of my solution did not need to be taken. This was because the solution of calcium hydroxide they used was saturated, and therefore they measured the temperature of the saturated solution along with its solubility, due to the fact that the solubility of saturated substances varies with temperature. This procedure will not be necessary in my particular experiment as the solution I will use will be far from saturated. Safety measures were observed and taken into account by looking at the hazard card for calcium hydroxide. I found the substance to have minimal hazards, especially when diluted in a non-saturated solution, and thus concluded the only precaution needed to be taken was to wear eye protection during handling of the solution. ...read more.

Middle

+ (2 x 1.0) = 74.1 Therefore number of moles present = 1/74.1 = 0.013495 mol To dilute the 2.0mol dm-3 solution to 0.01mol dm-3 deionised water will be used to eliminate the possibility of impurities being present within the solution, the probability of this increasing would have been increased if tap water had been used. An entire decimetre of solution was not required for this investigation, therefore only 500cm3 was made up. The dilution was carried out accordingly; 10.00cm3: 1000.00cm3 = 0.02mol dm-3. Therefore 5.00cm3: 1000.00cm3 = 0.01mol dm-3. Therefore 2.50cm3: 500.00cm3 = 0.01mol dm-3. For this dilution a graduated pipette will be used to accurately measure 2.50cm3 of acid, following this the deionised water will be added until the bottom of the meniscus rests on the 500cm3 mark. The lid will then be firmly placed on the volumetric flask and the solution will be shaken well, at least 20 shakes to ensure that the concentration of acid is equally distributed throughout the solution. Prior to pouring the acid into the burette a small funnel will be placed into the top to aid accurate pouring, ensuring none of the solution is wasted. ...read more.

Conclusion

24.20 48.50 24.25 Initial burette reading (cm3) 0.00 24.20 0.00 Titre (cm3) 24.20 24.30 24.25 Average titre = 24.25cm3 ((24.20 + 24.20 + 24.25) / 3) Analysis The balanced equation: 2HCl (aq) + Ca (OH) 2(aq) --> CaCl2 (aq) + 2H2O (l) Therefore to find the concentration of the limewater I obtained the average titre, and then worked out the number of moles of hydrochloric acid that were used using the equation: No. of moles (mol) = Concentration (mol dm-3) x Volume (dm3 Therefore 0.01 x 0.02425 = 0.0002425mol. To work out the number of moles of limewater used, the ratio of limewater to hydrochloric acid is 1:2, therefore 0.0002425/2 = 0.00012125. To work out the concentration of the limewater this figure is divided by the volume of limewater used using the equation: Concentration (mol dm-3) = No. of moles (mol) / Volume (dm3). Therefore 0.00012125/0.025 = 0.00485. To work out the concentration in g dm-3 we must first obtain the molar mass of calcium hydroxide which is 74.1. Using the equation: Mass (g) = Number of moles (mol) x Molar mass Therefore 0.00485 x 74.1 = 0.359385gdm-3. This being only accurate to approximately 0.36gdm3 due to the limited precision of the apparatus used. ...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

# Related GCSE Aqueous Chemistry essays

1. ## How much Iron (II) in 100 grams of Spinach Oleracea?

x 7.27 cm3 1000 The volume of the average titre is divided by 1000 to change the units from cm3 to dm3. Moles = 0.00018175 mol dm-3 The ratio of Potassium Manganate (VII) (aq) to Iron (II) (aq) is 3:5 and therefore to work out the mols of Iron (II)

2. ## The Use of Volumetric Flask, Burette and Pipette in Determining the Concentration of NaOH ...

NaOH + HCl -> NaCl + H2O Materials and Apparatus 50cm Burette Phenolphthalein Solution HCI Solution (1.000 x 10-2M) Watch Glass H2SO4 Solution (1.000x10-2M) Ring Stand 500ml Beaker NaOH Solution 25ml Volumetric Flask Pipette Bulb Funnel 250cm Erlenmeyer flask 20cm or 25cm Pipette Distilled water Suction Experimental Procedures 1.

1. ## The Use of Volumetric Flask, Burette and Pipette in Determining the Concentration of NaOH ...

0.00 5.00 Normal reading 25.50 25.50 25.60 30.20 NaOH volume 25.50 25.50 25.60 25.20 25.43 Analysis & Calculations: 1. Titration of NaOH with HCL (a) Mean Titre Average = X1 + X2 + X3 --------------- 3 = 11.80 + 12.00 + 11.80 --------------------------- 3 = 11.87cm� (b)

2. ## Determine the concentration of lime water.

I repeat this procedure 4 times until my target of 0.125 moles is achieved. When you have obtained the correct concentration of Hydrochloric acid you can proceed with the experiment. I set up the following apparatus: In the flask I have used 25.0cm3 of limewater and a few drops of methyl orange.

1. ## Determining the concentration of a limewater solution by volumetric analysis

Start releasing the acid in single drops when the purple solution in the flask begins to turn colourless and when the solution is completely colourless stop adding hydrochloric acid as the endpoint has been reached. Using this first attempt as a test run to get used to the procedure and

2. ## Find the concentration of limewater solution Titration

a damp paper towel and then mop up using a dry paper towel. The indicator being used, if it is methyl orange, also has its dangers so it should be stored in a sealed container in a cool environment. When using the methyl orange ensure that all doors and windows are open to provide good ventilation in the room.

1. ## determining the concentration of a limewater solution

Ca(OH)2 (aq) + 2HCl (aq) � CaCl2 (s) + 2H2O(l) The above equation shows that to neutralise the limewater, the ratio of Ca(OH)2 : HCl must be 1:2. This means that to have an equal amount of the limewater solution and dilute hydrochloric acid neutralising each other I will need to dilute

2. ## The aim of my experiment is to find the exact concentration of limewater. In ...

Begin by preparing the burette. The inside of the burette will be rinsed thoroughly with distilled water, including the portion below the tap. When rinsed the washings should be tipped away and the process should be repeated again to make sure that the burette is free from impurities that the burette may have accumulated inside it when it is not in use.

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