Sciencemadness Discussion Board - Basic Laboratory Techniques

Basic Laboratory Techniques

Sandmeyer - 31-12-2005 at 05:37

Here follows a collection of videos covering essential lab techniques. Files were originaly posted to a russian board by Scienthesis.

Basic Laboratory Techniques (50.8 mb)

http://rapidshare.de/files/10153321/Basic_Laboratory_Techniq...

When rapidshare dosen't work there is a bit slower alternative:

http://www.megaupload.com/?d=XTOK2FQ1

Laboratory Safety (1,95 MB)

http://rapidshare.de/files/10153424/Laboratory_Safety.rar.ht...

or

http://www.megaupload.com/?d=OZG3R9SA

These, as well as videos on other topics in practical organic chemistry can be selected from left frame in the following link:

http://www.chem.cuhk.edu.hk/lab_technique.asp

Darkblade48 - 31-12-2005 at 09:53

That's interesting, I have a similar page with almost exactly the same techniques, but it's from the Department of Chemistry, from the University of Hong Kong.

http://www.chem.cuhk.edu.hk/lab_technique_2basic.htm

The video itself is in Chinese, but it has English captions.

The_Davster - 31-12-2005 at 13:02

Another Universities Lab techniques page :
http://www.chem.ualberta.ca/~orglabs/videos/Videos.htm

chromium - 31-12-2005 at 17:29

Thanks for video links! Those are very usefull (for me at least). Does anyone know more of such web sites?

[Edited on 1-1-2006 by chromium]

fluting filter paper

Magpie - 31-12-2005 at 21:30

Darkblade I watched the video on paper fluting and it is the only instruction I've seen that gives a truly symmetrical 16 section flute. The trouble is your little buddy is too fast and I can't follow her moves. Happy New Year anyway. Now go out and set off some firecrackers.

edit: ...ahem, I watched the 250K version and it is much better (sorry).

[Edited on 1-1-2006 by Magpie]

Darkblade48 - 1-1-2006 at 12:34

It's very difficult in trying to describe how to properly flute a piece of filter paper, but it's kinda like origami. Really, all you are doing is folding the little circle into quarters and then lifting one of the quarters up and then "flattening" it....

It's hard to describe, but once you get the hang of it, it's actually quite simple to do, and it makes (gravity) filtration a lot easier.

The_Davster - 1-1-2006 at 13:01

I think I learned fluted paper from vogel, it took me a few tries to get it right. It gives pretty even flutes, except for a smaller one on each side.

12AX7 - 1-1-2006 at 13:16

Usually, when I want to fold some paper I just fold it twice, evenly (starting with a square, fold it in half, then fold the length in half, yielding a four layer square of half the dimensions of the original square), then open the top layer. Bending it out finds a 45 degree cone, with a lot of waste around the sides yes but it's quick.

If I'm feeling unusually lazy I just moisten it then push it into the jar I'm filtering into... viola, auto fluted paper... LOL

Tim

Magpie - 1-1-2006 at 14:59

I practiced on 5" circles of paper yesterday starting with procedures in my lab manuals. Both of these gave a 16 sector flute but with the two "boxes." While serviceable these lack elegance.

The Hong Kong demo at 250K is quite good and gives a 16 sector flute without the 2 "boxes." With a little practice anyone can do it.

thalium - 2-1-2006 at 03:31

I made it!!! 16 sector flute, no boxes

Darkblade48 - 2-1-2006 at 10:41

What boxes are we speaking of? Everytime I flute my filter paper, I get a neat 16 sectionned fluted piece of filter paper with triangles

Maybe it's just because I've practiced on a lot of pieces of paper first

Magpie - 2-1-2006 at 20:53

As you say it is hard to put into words.

Fold it with 16 equal sectors to form a fan. From an end view it will have a perfect 8-sided zig-zag. When opened there are 2 boxes.

The_Davster - 3-1-2006 at 00:35

Tip: fold those boxes in, you get a couple of smaller flutes. It is the way I learned it out of the book I learned it from.

[Edited on 4-1-2006 by rogue chemist]

Magpie - 3-1-2006 at 14:43

Yes, rogue, I've seen this technique also. It has the advantage of being much faster than the perfect Hong Kong fold.