Carry out titration and colorimetry to determine the
concentration of solutions
Introduction
For this assignment I will be looking at the experiment titration, to precisely determine
the concentration of sodium hydroxide. In order to do this, I will need to calibrate the
equipment I will be using, such as the pH meter and any balances. And make sure that
the chemicals are safe to use. I will also be looking at colorimetry and how to precisely
determine the concentration of copper sulphate.
Aim
Undertake titration and colorimetry to determine the concentration of solutions.
Standard solution
A standard solution is a solution that has a known concentration and is produced from
a primary standard (a stable compound that is highly soluble in water, has a high
molar mass, and is also high in purity) this is weighed precisely and made up to a
volume that is fixed.
A standard solution is also used to then assist and identify concentrations of other
solutions that have unknown concentrations. (Royal Society Of Chemistry, n.d.)
Aim
To determine the concentration of unknown solutions. (Make 250cm3 of 0.4mol/dm3
sodium carbonate solution).
Equipment
1. Pipette
2. Distilled water
3. Beaker
4. Digital balance
5. Weighing boat
6. Volumetric flask
7. Sodium carbonate
8. Spatula
9. Glass rod
10.Funnel
11.Label and marker
12.goggles
Method
1. Rinse all the equipment before use with distilled water, for the most accurate
results.
LEARNER ASSESSMENT SUBMISSION AND DECLARATION
, 2. Measure out 10.6g of sodium carbonate with a weighing boat using a digital
balance, making sure the digital balance reads zero before pouring the
sodium carbonate.
3. Transfer the solid sodium carbonate to a beaker making sure all the sodium
carbonate has been transferred.
4. Add 150cm³ of distilled water to the same beaker and stir it well until the
sodium carbonate has dissolved in the water
5. Transfer the solution to a 250cm³ volumetric flask.
6. Fill the rest of the volumetric flask with distilled water up to the faint line
that is indicated on the volumetric flask.
7. Close the volumetric flask and mix the solution gently by turning it upside
down and gently turning it back up again, with the distilled water.
Risk assessment
Hazards Possible harm Precaution
Sodium carbonate Can cause eye irritation Wear goggles
Digital balance Electric shocks Avoid playing around with
broken weighing balances
Volumetric flask/beaker If it breaks it can cut the Avoid playing around with
(glassware) skin glassware and wear gloves
Calculations
Mass = moles x molar mass
Moles = concentration x volume
Moles = 0.4 mol/dm3 x 0.25dm3
Moles = 0.1mol
Molar mass of Na2CO3 = 105,9888 g/mol
= 106 g/mol
Mass = moles x molar mass
Mass = 0.1mol x 106g/mol
Mass = 10.6g
Evaluation
The standardisation I did was straightforward and easy to make, as I only had to mix
sodium carbonate and distilled water to form sodium hydroxide, the instructions were
easy to follow. However, I could’ve done more than one standardisation to have a
more accurate set of results and to also be able to have more results from my titration
experiment.
To view the accuracy of my results I compared them with two of my peers, both of
those results were also 10.6 grams of mass needed to make Na2CO3 this further
Titration
LEARNER ASSESSMENT SUBMISSION AND DECLARATION
, Titration is an experiment where a solution with a known concentration is added to
another solution with an unknown concentration to find out its concentration. (LibreTexts
Chemistry, 2022)
Titration using an indicator
Titration refers to the act of adding a known solution to an unknown solution to find
out the concentration of that solution. An indicator is the final point is indicated either
by the physical change in the reaction or by the addition of an auxiliary reagent is
known as an indicator. (BYJU'S, 2023)
Aim
To carry out a titration using different chemicals: dilute hydrochloric acid, dilute
sodium hydroxide solution, and phenolphthalein indicator
Equipment
1. Volumetric Pipette
2. Burette
3. Conical flask
4. Pipette filler
5. Funnel
6. Pipette
7. Volumetric Pipette
8. Dilute hydrochloric acid
9. Dilute sodium hydroxide
10.Methyl orange
11.White tile
12.Goggles
Method (Anon., 2023)
1. set the burette in a burette holder
2. Use the pipette to accurately measured 25ml of alkali.
3. Place the alkali in a conical flask and then add five drops of the
phenolphthalein indicator (methyl orange).
4. Fill the burette with dilute hydrochloric acid. remove any air bubbles
inside the burette and ensure the burette is vertical.
5. Slowly turn the tap on the burette to add the dilute hydrochloric acid.
6. Swirl the mixture until it changes colour, from orange to pink and then
close the tap. Using the white tile will make it easier to see the colour
change.
7. Note the volume on the burette.
8. Repeat this until you have at least three results.
yellow orange red
alkali endpoint acid
Risk assessment
Hazards Possible harm Precaution
Dilute sodium hydroxide Can cause skin and eye Wear goggles, lab coat, and
solution irritation gloves
LEARNER ASSESSMENT SUBMISSION AND DECLARATION
concentration of solutions
Introduction
For this assignment I will be looking at the experiment titration, to precisely determine
the concentration of sodium hydroxide. In order to do this, I will need to calibrate the
equipment I will be using, such as the pH meter and any balances. And make sure that
the chemicals are safe to use. I will also be looking at colorimetry and how to precisely
determine the concentration of copper sulphate.
Aim
Undertake titration and colorimetry to determine the concentration of solutions.
Standard solution
A standard solution is a solution that has a known concentration and is produced from
a primary standard (a stable compound that is highly soluble in water, has a high
molar mass, and is also high in purity) this is weighed precisely and made up to a
volume that is fixed.
A standard solution is also used to then assist and identify concentrations of other
solutions that have unknown concentrations. (Royal Society Of Chemistry, n.d.)
Aim
To determine the concentration of unknown solutions. (Make 250cm3 of 0.4mol/dm3
sodium carbonate solution).
Equipment
1. Pipette
2. Distilled water
3. Beaker
4. Digital balance
5. Weighing boat
6. Volumetric flask
7. Sodium carbonate
8. Spatula
9. Glass rod
10.Funnel
11.Label and marker
12.goggles
Method
1. Rinse all the equipment before use with distilled water, for the most accurate
results.
LEARNER ASSESSMENT SUBMISSION AND DECLARATION
, 2. Measure out 10.6g of sodium carbonate with a weighing boat using a digital
balance, making sure the digital balance reads zero before pouring the
sodium carbonate.
3. Transfer the solid sodium carbonate to a beaker making sure all the sodium
carbonate has been transferred.
4. Add 150cm³ of distilled water to the same beaker and stir it well until the
sodium carbonate has dissolved in the water
5. Transfer the solution to a 250cm³ volumetric flask.
6. Fill the rest of the volumetric flask with distilled water up to the faint line
that is indicated on the volumetric flask.
7. Close the volumetric flask and mix the solution gently by turning it upside
down and gently turning it back up again, with the distilled water.
Risk assessment
Hazards Possible harm Precaution
Sodium carbonate Can cause eye irritation Wear goggles
Digital balance Electric shocks Avoid playing around with
broken weighing balances
Volumetric flask/beaker If it breaks it can cut the Avoid playing around with
(glassware) skin glassware and wear gloves
Calculations
Mass = moles x molar mass
Moles = concentration x volume
Moles = 0.4 mol/dm3 x 0.25dm3
Moles = 0.1mol
Molar mass of Na2CO3 = 105,9888 g/mol
= 106 g/mol
Mass = moles x molar mass
Mass = 0.1mol x 106g/mol
Mass = 10.6g
Evaluation
The standardisation I did was straightforward and easy to make, as I only had to mix
sodium carbonate and distilled water to form sodium hydroxide, the instructions were
easy to follow. However, I could’ve done more than one standardisation to have a
more accurate set of results and to also be able to have more results from my titration
experiment.
To view the accuracy of my results I compared them with two of my peers, both of
those results were also 10.6 grams of mass needed to make Na2CO3 this further
Titration
LEARNER ASSESSMENT SUBMISSION AND DECLARATION
, Titration is an experiment where a solution with a known concentration is added to
another solution with an unknown concentration to find out its concentration. (LibreTexts
Chemistry, 2022)
Titration using an indicator
Titration refers to the act of adding a known solution to an unknown solution to find
out the concentration of that solution. An indicator is the final point is indicated either
by the physical change in the reaction or by the addition of an auxiliary reagent is
known as an indicator. (BYJU'S, 2023)
Aim
To carry out a titration using different chemicals: dilute hydrochloric acid, dilute
sodium hydroxide solution, and phenolphthalein indicator
Equipment
1. Volumetric Pipette
2. Burette
3. Conical flask
4. Pipette filler
5. Funnel
6. Pipette
7. Volumetric Pipette
8. Dilute hydrochloric acid
9. Dilute sodium hydroxide
10.Methyl orange
11.White tile
12.Goggles
Method (Anon., 2023)
1. set the burette in a burette holder
2. Use the pipette to accurately measured 25ml of alkali.
3. Place the alkali in a conical flask and then add five drops of the
phenolphthalein indicator (methyl orange).
4. Fill the burette with dilute hydrochloric acid. remove any air bubbles
inside the burette and ensure the burette is vertical.
5. Slowly turn the tap on the burette to add the dilute hydrochloric acid.
6. Swirl the mixture until it changes colour, from orange to pink and then
close the tap. Using the white tile will make it easier to see the colour
change.
7. Note the volume on the burette.
8. Repeat this until you have at least three results.
yellow orange red
alkali endpoint acid
Risk assessment
Hazards Possible harm Precaution
Dilute sodium hydroxide Can cause skin and eye Wear goggles, lab coat, and
solution irritation gloves
LEARNER ASSESSMENT SUBMISSION AND DECLARATION
