Practical Techniques In Organic Chemistry Flashcards
Quickfit apparatus
Pear shaped flask Receiver Screw tap adaptor Condenser Still head
Heating under reflux
Prepare organic liquid without boiling off solvent reactants, products
Heat to overcome AE
Reaction can be heated at fixed temperature
Heating mantle to be used if organic compound flammable
Flask clamped by neck
Enables liquid to be continually boiling whilst reaction occurs
Prevents volatile compounds from escape and flask from boiling dry
Antibumping granules
Control boiling, prevent large bubbles from forming, glassware vibrates
Condenser
Upright position, clamped loosely
Keep top open, release gas pressure
Water enters from bottom, ensure that jacket is always full
Distillation
Purify compound from impurities, separates by boiling points
Use as many clamps necessary, support both ends
Water always enters from lowest point
Not upright, receiver open
Vapour moves out of flask, condensed
Liquid drips into collecting flask
Removing water from organic products
2 immiscible layers
Close separating funnel tap, place a stopper and invert
Allow layers to settle, add water to see which layer is aqueous
Remove aqueous layer into waste beaker
Remove organic layer into another beaker
Acid impurities
Add NaCO3, shake in separating funnel
React to form CO2, gas must be released by releasing stopper
NaCO3 layer removed and organic layer washed with H2O before separating into 2 funnels
Desiccating agents for drying the organic product
Anhydrous calcium chloride, hydrocarbons
Anhydrous calcium sulphate, general
Anhydrous magnesium sulphate, general
Drying the organic product
Add drying agent, mix
Place stopper, prevent evaporation of products
Add more agent until solid is dispersed in solution as fine powder
Decant into another flask, dry=clear
Redistillation
If organic liquids have similar boiling points, product is purer
