requied prac

What dos it mean to heat under reflux

Keeping something on the boil but having a condenser vertically above volatile substance - boil - condense - back into mixture

Why is the tube attached to the bottom. The condenser

When water is turned on - be pushed up against gravity to completely fill the condenser - all reactants that evaporate can condone effectively

How do u oxidised ethanol

Using acified dichrmoate solution in a pear shaped flask

Why do u have no stopper

Avoid risk of pressure building up and explosion

Why do you add anti bumping granules

Provide large surface area so that small bubbles form not large (which could push out of condenser)

What is the colour change

Red to green

Red - dichromate

Green - ethanol oxidised and also bubbles and steam = ethanol to ethanal

How do u do the reflux of ethnal to ethanoic acid

Pear shaped in a water bath over Bunsen Burner (gentle heating and remain in reflux )

Distill ethanoic acid - still head nd thermometer bulb is level with junction of condenser - it will take the temp of vapour of that point

Till head = add to condenser to distill

Collect product with beaker

How to test is its ethanoic acid

Smell for vinegary smell

Chemical test - universal indicator

Ad sodium carbonate - ethanoic acid should fizz and release coo2

What are the differences between reflux and distillation

D= separation and purification

R = controls chemical reactions

D = separates components based on volatility

R = allow a reaction to proceed under controlled conditions

D= shorter

R= longer

D= produces purified product

R= reaction completion