Tag: science

Autumn Term One Review

For the last 8 weeks, I have been settling back into my school routine (COVID-19 edition). Even through the last few weeks, school have made many changes such as now making face coverings compulsory in all shared areas as well as making the loud noisy common room a quieter study area. It is very weird having my science lessons in a DT room and my Maths lessons in random classrooms however luckily the majority of my Chemistry classes are in a science lab.

For the first few days of the year I was very stressed over returning to school. We were sent our reopening plan and I was unhappy with the changes in place and was very anxious however, I have slowly adjusted to school. It is not as strict as it was before Summer but there are specific doors and areas of the school we are allowed in. The weather has been fairly warm so I have been able to sit outside rather than in the hot common room. However, as it neared the end of September and start of October, the weather got colder so I have been sitting inside more often.

school work

This term at school, we have been focusing on sorting out UCAS and our personal statements as well as sorting out my American applications. Halfway through the term we had Recovery Assessments to catch up on our work from March. These tests were low stakes so it was more for the teachers to check our understanding compared to being grades. As part of my USA application, I have been partaking in many virtual webinars in my evenings and attending UK open days.

I have also been continuing my extracurricular activities from dancing weekly on a Wednesday evening to completing virtual Beaver meetings on a Monday. I also am counting watching Home and Away as an extracurricular! Over the past month or so, I have nearly finished watching The Flash season six and participated in DC’s virtual comic con.

Overall, this term has improved as the weeks have past. The leaves are falling and soon we will be converting back to GMT time. Summer is over, and autumn is in swing getting closer and closer to Christmas. During half term, I am planning to complete some school work, revise and finish up my university applications. On top of this, I am going to relax and carve pumpkins whilst decorating the house for Halloween.

How to prepare cyclohexane.

A while back in A level Chemistry we have been completing a practical on preparing a cyclohexane. Today’s blog post I will show the practical instructions with photos of our set ups and final product. This is to celebrate the ending of British Science Week 2020!

Part 1: preparation

Distillation apparatus
  1. Add 10cm3 of cyclohexane to a small round bottom or pear-shaped flask (CARE: don’t get it on your skin. Don’t inhale it. Keep away from naked flame.)
  2. Slowly add 4cm3 of concentrated phosphoric(v) acid and mix thoroughly (CARE: don’t get it on your skin. Mix slowly to prevent it getting too hot due to it being an exothermic reaction.)
  3. Add a few anti-bumping granules to the mixture, then set up the apparatus for reflux alongside an electric heater or sand bath (CARE: avoid splashing when adding granules.)
  4. Heat the mixture under reflux at 70oc for 15 minutes, adjust the heating and cooling rates to ensure that all condensation occurs in the lower half of the condenser (CARE: avoid water contact with electricity.)
  5. Stop heating and allow the glassware to cool for a few minutes (CARE: don’t touch the hot glass whilst it cools.)
  6. Rearrange the apparatus for distillation
  7. Raise the temperature and distil very slowly, collecting the distillate which comes over between 70oc and 90oc (CARE: don’t raise the temperature too fast. Don’t touch any apparatus which is hot.)

Part 2: purification

The pure cyclohexene we made
  1. Add an equal volume of saturated sodium chloride solution to the distillate in a separating funnel, shake gently and release any pressure build-up (CARE: avoid pressure build up and hence an explosion.)
  2. Allow the layers to separate and then discard the lower aqueous layer
  3. Wash the organic layer with an equal volume of water and discard the lower aqueous layer
  4. Run the remaining organic layer into a small conical flask
  5. Add a few lumps of anhydrous calcium chloride and swirl the mixture – if the liquid does not become clear, add more anhydrous calcium chloride and swirl again (CARE: avoid skin contact.)
  6. Finally decant the clear liquid into a weight container (CARE: avoid skin contact.)
  7. Reweigh the container and find the mass of cyclohexane that you have prepared (CARE: avoid skin contact.)
Using Bromine water to confirm that the product was an alkene as the bromine water should turn form orange to colourless when an alkene is present.

Part 3: organic functional group identification

  1. Test for the presence of carbon-carbon double bond in the product