CP6 - Chlorination Of 2-methylpropan-2-ol Using Conc HCl Flashcards
How do you form the crude product?
• Add conc. HCl and 2-methylpropan-2-ol to a conical flask.
Put the rubber bung in and swirl the flask.
• Open the bung to release the pressure. Repeat this regularly over 20 minutes.
• Add some anhydrous CaCl, and shake.
• At this point, there should be two distinct layers.
• Upper layer = organic product. Lower layer = aqueous layer
How do you separate the organic layer from the aqueous layer?
• Transfer the contents of the flask to a separating funnel.
• Allow the layers to separate and remove the lower (aqueous) layer by opening the tap.
• Keep the organic layer in the separating funnel.
How do you remove the unreacted HCl?
• Add a solution of NaHCO, to remove the unreacted HC. Swirl. Stopper the separating funnel and shake it.
• Invert and open the tap to release pressure. Repeat a few times.
• Remove the stopper and run off the aqueous layer.
Then, run the organic layer into a clear conical flask.
How do you remove any water from the organic liquid?
Add some anhydrous Na,SO, because it acts as a drying agent.
How do you purify the product?
• Distillation.
• This separates the products based on boiling point.
• Collect the liquid boiling between 50°C and 52°- this should be the pure product.
What is distillation?
• Distillation is a technique where the heating of a liquid to create a vapour is cooled by a condenser, causing the gas to condense into a liquid and drip into a separate flask.
• The different substances will be separated by boiling point/volatility.
What equipment is used for distillation?
Quickfit apparatus:
• Pear-shaped or round-bottomed flask with a liebig condenser, still head, stopper, receiver adaptor, fitted with a thermometer and collection vessel.
What does a diagram of Quickfit apparatus set up for distillation look like?
Draw and check notes
Why are anti-bumping granules used in distillation?
To allow smooth boiling. They prevent the appearance of bubbles caused by vapour in the hot liquid which would cause splashing up the sides of the flask.
What are some potential hazards and risks in the laboratory?
Bunsen burner - Burns - Keep away from flammable chemicals and away from the edge of the desk.
2-methylpropan-2-ol and 2-chloro-2-methyl propane - Flammable and harmful - Wear eye protection. Keep away from the edge of the desk and from an open flame. Don’t ingest or inhale.
HCI - Corrosive - Don’t inhale or ingest. Wear gloves when handling. Wear safety glasses. Carry out this part of the experiment in a fume cupboard.
Glassware i.e. beakers - May break and cut you - Handle with care and keep away from edge of the desk.
