I BTEC Applied Science I Chemistry I Unit 4 I Laboratory Techniques and Their Applications I
Learning Aim C I Making Aspirin I
What is Aspirin (2-ethanoyloxybenzoic acid)?
Aspirin (2-ethoxybenzoic acid) is a commonly used analgesic, or pain reliever. It is used for temporary pain
relief for headaches, pain, fever, arthritis, and other uses. It is produced through the process of chemical
synthesis; it reacts with ethanoic anhydride and 2-hydroxybenzoic acid. It can be made in multiple ways.
One of the most basic methods is to use oil of wintergreen, which is made by distilling the plant's leaves. [1]
[1]
As
pirin Structure
What is Reflux ?
Reflux is a method that involves heating the reaction mixture to the boiling point (oC) of the solvent's
reaction and then using a condenser to recondense the vapours back into the pear-shaped flask. But for
making aspirin, we will use a round-bottom flask. This gives the reaction plenty of time to complete itself. [2]
Reflux is a type of technique that allows organic substances to be heated for a longer period of time while
also minimising the loss of substances in the atmosphere. By keeping a high boiling point temperature,
reflux is still used to make alcoholic beverages. The temperature is controlled by the condenser’s outlet.
Secondary condensers are substances with low boiling points. This produces high-quality alcoholic
beverages, making sure that unreacted substances are returned to the reflux still. [2]
[2]
Reflux Diagram
1
,Part 1: Preparation Of 2-Hydroxybenzoic Acid:-
Equipment:-
- Anti-Bumping Granules
- Distilled Water
- 2.5cm3 Oil Of Wintergreen
- Sodium Hydroxide (NaOH(aq))- 2.0 mol dm-3
- Hydrochloric Acid (HCl(aq))- 2.0 mol dm-3
- 2X Measuring Cylinder- 10cm3 and 50cm3
- Ice Cubes or Ice Water
- Beaker- 100cm3
- Round Bottom Flask- 50cm3
- Liebig Condenser and Tubing
- Stirring Rod
- Watch glass
- Pipette
- Apparatus for Filtration
- Test Tube with Lid
- Measuring Scale
- Heating Mantle
- Marker Pen
- pH Indicator Paper
Method:-
1. To begin, connect the round bottom flask, Liebeg condenser, and tubing to the quick-fit apparatus
for reflux.
2. Measure 2.5cm3 oil of wintergreen in a 10cm3 measuring cylinder. Afterwards, measure the mass of
oil of wintergreen with the measuring cylinder, using a measuring scale.
3. Pour the oil of wintergreen into the 50cm3 round bottom flask. Then measure the measuring
cylinder’s mass afterwards.
4. Measure about 25cm3 of 2.0 mol dm-3 Sodium Hydroxide (NaOH), using a 50cm3 measuring
cylinder. Fill the pear-shaped flask halfway with Sodium Hydroxide. Add a few Anti-Bumping
Granules.
5. Using a heating mantle, reflux the mixture for 30 minutes.
6. Allow the mixture to cool before pouring it into a 100 cm3 beaker and submerging it in an ice bath.
7. Dropwise add 2.0 mol dm-3 Hydrochloric Acid (HCl) to the reaction mixture. Stir the mixture using a
stirring rod. Regularly test the mixture with a pH indicator paper. Continuously add the acidic
solution until the mixture has become acidic.
8. Using filtration, filtrate the solid product produced from the reaction mixture. Wash the product with
small drops of distilled water.
9. Record the mass of the watch glass before transferring the solid product into the watch glass. Leave
the solid product to dry.
10. After the solid product has dried completely, record the mass of the solid product and the watch
glass together. Then transfer the solid product into a clean and dry test tube.
2
, Risk Assessment: Part 1: Preparation of 2-Hydroxybenzoic Acid:-
Overall, the risk is MEDIUM.
Risk Why is it a risk ? Grade (Low , Medium , How to prevent it?
High)
[3]
Anti - Bumping ● It is irritating to Low ● Wear safety
Granules the eyes. glasses.
● It irritates the ● Put on protective
skin. gloves.
● If ingested, it is ● If inhaled, move
toxic. the person to
● When inhaled, it fresh air, or open
is toxic. all windows and
air out the room
if breathing
stops.
● Wash the eye
gently for about
10 minutes with
running tap
water.
● If the skin is
contaminated,
remove all
contaminated
clothing as soon
as possible -
unless it is stuck
to the skin.
● For about 10
minutes, gently
wash the
contaminated
area with running
tap water.
Glassware ● Broken glass can Low ● Handle
easily cause glassware with
cuts. caution during
● Glass can experiments.
expand as a ● Handle
result of chemicals that
chemical are fragile in
reactions that glass.
generate heat. ● If broken glass
● Glass fragments has pierced your
can pierce the skin, go to the
skin. hospital and
consult a doctor.
● Remove any
broken glass
from the bench
or the floor.
[4]
Sodium Hydroxide ● Burns the skin High ● Wear eye
(NaOH(aq)) severely. protection -
2.0 mol dm-3 ● It is harmful to goggles.
3
Learning Aim C I Making Aspirin I
What is Aspirin (2-ethanoyloxybenzoic acid)?
Aspirin (2-ethoxybenzoic acid) is a commonly used analgesic, or pain reliever. It is used for temporary pain
relief for headaches, pain, fever, arthritis, and other uses. It is produced through the process of chemical
synthesis; it reacts with ethanoic anhydride and 2-hydroxybenzoic acid. It can be made in multiple ways.
One of the most basic methods is to use oil of wintergreen, which is made by distilling the plant's leaves. [1]
[1]
As
pirin Structure
What is Reflux ?
Reflux is a method that involves heating the reaction mixture to the boiling point (oC) of the solvent's
reaction and then using a condenser to recondense the vapours back into the pear-shaped flask. But for
making aspirin, we will use a round-bottom flask. This gives the reaction plenty of time to complete itself. [2]
Reflux is a type of technique that allows organic substances to be heated for a longer period of time while
also minimising the loss of substances in the atmosphere. By keeping a high boiling point temperature,
reflux is still used to make alcoholic beverages. The temperature is controlled by the condenser’s outlet.
Secondary condensers are substances with low boiling points. This produces high-quality alcoholic
beverages, making sure that unreacted substances are returned to the reflux still. [2]
[2]
Reflux Diagram
1
,Part 1: Preparation Of 2-Hydroxybenzoic Acid:-
Equipment:-
- Anti-Bumping Granules
- Distilled Water
- 2.5cm3 Oil Of Wintergreen
- Sodium Hydroxide (NaOH(aq))- 2.0 mol dm-3
- Hydrochloric Acid (HCl(aq))- 2.0 mol dm-3
- 2X Measuring Cylinder- 10cm3 and 50cm3
- Ice Cubes or Ice Water
- Beaker- 100cm3
- Round Bottom Flask- 50cm3
- Liebig Condenser and Tubing
- Stirring Rod
- Watch glass
- Pipette
- Apparatus for Filtration
- Test Tube with Lid
- Measuring Scale
- Heating Mantle
- Marker Pen
- pH Indicator Paper
Method:-
1. To begin, connect the round bottom flask, Liebeg condenser, and tubing to the quick-fit apparatus
for reflux.
2. Measure 2.5cm3 oil of wintergreen in a 10cm3 measuring cylinder. Afterwards, measure the mass of
oil of wintergreen with the measuring cylinder, using a measuring scale.
3. Pour the oil of wintergreen into the 50cm3 round bottom flask. Then measure the measuring
cylinder’s mass afterwards.
4. Measure about 25cm3 of 2.0 mol dm-3 Sodium Hydroxide (NaOH), using a 50cm3 measuring
cylinder. Fill the pear-shaped flask halfway with Sodium Hydroxide. Add a few Anti-Bumping
Granules.
5. Using a heating mantle, reflux the mixture for 30 minutes.
6. Allow the mixture to cool before pouring it into a 100 cm3 beaker and submerging it in an ice bath.
7. Dropwise add 2.0 mol dm-3 Hydrochloric Acid (HCl) to the reaction mixture. Stir the mixture using a
stirring rod. Regularly test the mixture with a pH indicator paper. Continuously add the acidic
solution until the mixture has become acidic.
8. Using filtration, filtrate the solid product produced from the reaction mixture. Wash the product with
small drops of distilled water.
9. Record the mass of the watch glass before transferring the solid product into the watch glass. Leave
the solid product to dry.
10. After the solid product has dried completely, record the mass of the solid product and the watch
glass together. Then transfer the solid product into a clean and dry test tube.
2
, Risk Assessment: Part 1: Preparation of 2-Hydroxybenzoic Acid:-
Overall, the risk is MEDIUM.
Risk Why is it a risk ? Grade (Low , Medium , How to prevent it?
High)
[3]
Anti - Bumping ● It is irritating to Low ● Wear safety
Granules the eyes. glasses.
● It irritates the ● Put on protective
skin. gloves.
● If ingested, it is ● If inhaled, move
toxic. the person to
● When inhaled, it fresh air, or open
is toxic. all windows and
air out the room
if breathing
stops.
● Wash the eye
gently for about
10 minutes with
running tap
water.
● If the skin is
contaminated,
remove all
contaminated
clothing as soon
as possible -
unless it is stuck
to the skin.
● For about 10
minutes, gently
wash the
contaminated
area with running
tap water.
Glassware ● Broken glass can Low ● Handle
easily cause glassware with
cuts. caution during
● Glass can experiments.
expand as a ● Handle
result of chemicals that
chemical are fragile in
reactions that glass.
generate heat. ● If broken glass
● Glass fragments has pierced your
can pierce the skin, go to the
skin. hospital and
consult a doctor.
● Remove any
broken glass
from the bench
or the floor.
[4]
Sodium Hydroxide ● Burns the skin High ● Wear eye
(NaOH(aq)) severely. protection -
2.0 mol dm-3 ● It is harmful to goggles.
3
