Wednesday, January 28, 2009

preparation of cyclohexene

Venue: 1st year Organic Chem Lab
Time: 9:20 a.m.

today we gonna do some organic experiment on how we can prepare cyclohexene from cyclohexanol. (disini saya mau ingatkan bahawa penggunaan perkataan 'cyclo' tiada kena mengena dengan sebarang watak dari komik x-men).

1) first, we will start the experiment by setup the main apparatus which is  fractional distillation column. to be remind here the process of setup the apparatus is quite complicated, so any aid from the lab technicion will be appreciate. (saya sendiri makan masa dalam 40 minit hanya duk setup benda ni)

2) the cyclohexanol and concerntrated sulphuric acid was added into the round cute bottomed flask. don't forget to add a few pieces of bumping granules. (utk mengelak gejala melatah dikalangan mahasiswa). heat the reaction mixture with small flame.
jaga api tu jgn deras sgt!
(this can be control by looking at the thermometer, kalo suhu lebih seratus maknanya ada benda asing lain selain air yg tersejat tu)



3) continue the heating and the distillation process until the mixture is completely dried.
(kering dah...)



distilate aka product



4) pour the distillate into a funnel to separate the hydrocarbon layer and the water. 
air tu buang skit je tau. kang lebih2 terbuang alkene tu plak!



5) pour the distillate into a conical flask and leave it to make it dry. (time ni leh sembang2 ngan lab technician. lebih baik lagi kalo guna waktu2 camni pi wat report yg tertangguh 2 3 minggu tu)
6) while waiting, we can setup a new one fractional distillation column. but this time we use the small one.  (distillate tadi tu leh taruh dlm distillation flask yang kiut miut ni)
jangan lupa panaskan lak..


7) continue the process until all the distillate was dry up. record the boiling point and the weight of the cyclohexene.

tadaa...
siap dah!
Product:
99.99% Cyclohexene






Sudut Muhasabah Diri! (caution in the lab)

1- Jangan terlalu lalai sampai tidak dapat nak bezakan antara chemicals dan pelarut biasa. dalam bahasa lain ialah LALAI.

cth: nadea telah mencampurkan bahan kimia dan air paip semasa memasang radas. hihihi...



2- Jangan terlalu excited nak balik awal (lab hari jumaat so lunch nasi ayam) sampai terpecah segala radas.

cth: kak elly yang every week basuh dan kemas paling awal tlah memecahkan radas yang berisi bahan kimia untuk kali ke berapa ntah. (uncountable, tiap2 minggu ada je benda dia pecahkan)
~FIN

4 comments:

Star-Piz said...

takde kes letup lagi ke kali ni?

yanee said...

antik nye lab korang.hahahha

'S' for something said...

suka utk sy nyatakan disini sy x suke sains..(kimia&fizik)thank god sy dpt kptsn yg agak baik dlm spm haha

sy x suke blajar bnda2 yg sy x nmpk huhu...

mint heartnet said...

apiz: kes letup meletup kena stay dlm meeting je ek! xleh rakam2 or bwak keluar!!!

yanee: bkn lab korg, lab kita la..

kak sha: bkn sume benda dlm lab tu x nampak, kalo terpecah apparatus yg mahal, kita leh nampak duit dlm akaun berkurang!