Entry 8

Todays Lab lesson...

I learned about simple distillation today.
Generalization: Systems have elements that interact with each other to perform a function. Systems follow rules.

Distillation
Simple distillation is used to purify a liquid by separating the solvent from the dissolved solutes.
1. It involves 2 stages and both are physical state changes.
2. Stage (1): The liquid or solution mixture is boled to vaporise the most volatile component in the mixture (liquid ---> gas).
3. Stage (2): The vapour is cooled by cold water in the liebig condenser to condense (gas ----> liquid) it back to liquid (the distillate) which is collated.

This is a diagram of simple distillation 
*Note that the distillate is pure water.

For my experiment, we used Coca-cola to be the solution. after the experiment was was left behind from the distillation were sugar, carbon and caffeine.

Some questions to think about...
1. Why does the water enter the condenser from the bottom and exit from the top?

This is to ensure that most of the water vapour is condensed and collected as liquid. If cold water enters from the top, it will not fill the condenser.

2. What is the function of boiling chips?

It is to make boiling point smooth.

3. Why is the bulb of the thermometer placed next to the sidearm?

This is to allow us to measure the temperature of vapour in order to identify the boiling point of the distillate.

Application

• Distillation can be used to purify water because the dissolve solids will not evaporate with the steam. 
• It can also be use to separate two miscible liquids with different boiling point. But it is ineffective if the boiling points of liquids are relatively close. 
• Distillation is not the only way we can obtain pure drinking water. NEWater production make use of two main separation steps- micro filtration and reverse osmosis. 

Isn't it so fascinating to see how pure water is being obtained!! I think that todays lab lesson was extremely fun and engaging it was also an eye-opener. 

We also learned additional information about fractional distillation. Both distillation methods are similar because both involve coiling and condensing and require heat energy. However they are also different as the simple distillation method has no fractionating column, however the fractional distillation has a fractionating column. 

This diagram is a setup of fractional distillation. The fractionating column can be seen above the round-bottom flask.  

Simple distillation and fractional distillation are used to separate the solvent from the solution(simple distillation), for fractional distillation it is to separate 2 miscible liquids. 

During the 1st part of the lesson i also finally got to experience handling chromatography paper and carry out an experiment!! (It was super exciting and interesting!) 

This was the colour i got from mixing distilled water with green food dye! A really pretty colour. Apparently, some lucky people got to have some yellow and pink on their chromatography paper too. 

For the second part of the lesson we did an online class activity called "are you good enough for it?" We had to work in groups of 4 and plan a suitable procedure for separating all the chemicals in the given mixture. My group is still in the midst of creating our powerpoint slide which one of our group members is in charge of. The other 3 of us are in charge of researching on the different chemicals. 

1. Iron filings

2. Iodine (sublimes when heated) 

3. Copper Sulphate

4. Calcium sulphate

5. Ammonium chloride (sublimes when heated) 

6. Lead (II) Bromide

For every single chemical we are suppose to find out its physical appearance, magnetic attraction, solubility in water and solubility in organic solvents. After that we also need to create a flow chart to show our proposed separation procedure. It is very interesting but also brain racking when we are unable to find out things about the chemicals. 

Alright, that's it for today, thank you for reading my blog!