pag 5 - distillation of a product from a reaction

What is the method of the [ractical of turning an alcohol into an alkene

What solution is used

And what do u add

Acidify potassium manage solution

Pour it into a pear shaped flask with a still head containing a thermometer

Attach to a condenser with a ice cooled vessel

Add anti bumping granules

Heat flask gently collect sample at boiling point of desired produc

For the practical of turning alcohol into Alkenes why is a cooled vessel used

Essential to reduce evaporation of products

What’d o u have to remember with distillation

What should u use withlammable substances

What should u make sure with the thermeometer

Why are anti bumping granules added

• electric heat or water bath

• Antibumping granules - prevent large bubbles forming

• Bulb of thermometer should be at T- junction to measure correct boiling point

Why dos water enter at the lowest point for distillation

Water enters a at lowest point and leaves at highest o go against gravity - ensures condense is filled with water

Why should the collection flask not be concealed at distillation

Collection flask shouldn’t be sealed

Not air tight cux when its heated the air inside the system expands and can crack

What’s the reagent used and conditions and observations when turning from a primary alcohol into an ldehyde

Reagent - potassium dichromate solution and dilute sulphuric acid

Conditions =-use limited amount of dichromate - warm gently and distill out the aldehyde as it form s

Observation - orange dichromate reduces to the green cr 3+ ion

What’s the method when turning from a primary alcohol into an aldehyde

10cm³ of dilute sulphuric acid in a flask and add about 3g of potassium dichromate and antibumping granules - shake and dont warm 1.5cm³ of propan-1-ol from dripping pipette and shake

Heat with distillation and slowly distill 2cm³ of liquid into test tube

Can then test for aldehyde with tollens reagent

What is the reagent and conditions when turning a primary alcohol into a carboxylic acid

Primary alcohol into a carboxylic acid

Reagent - potassium dichromate + sulphuric acid

Conditions - use excess dichromate and heat under reflux

What is the method of turning from a primary alcohol into a carboxylic acid?

How much water and what do u shake it with

What alcohol do u use and what should u add

What solution to u add to the alcohol

What do u do right at the end to the liquid

• 5cm³ of water in boiling tube + add 6g of sodium dichromate and shake to dissolve

• 1.5cm³ of propane-1-ol in flask and add water an antibumping granules

• Set up reflux apparatus

• Add 2cm³ of conc H2SO4 down condenser in drops

• Add sodium dichromate solution down condenser in drops using dropping pipette

• Energy released should make mixture boil

• When all s.dichromate sol has been addded - heat on low bunsen burner flame to keep boiling for 10 minutes

• Then distil 2-3cm³ of liquid into a test tube

When is reflux used and what is the condenser used for

Reflux is used when heating for long periods of time

The condenser is use to prevent organic vapour from escaping by condensing them back to liquids

(Never seal end of condenser - explode)