Difference between revisions of "Cold finger"
From Sciencemadness Wiki
(Created page with "{{Stub}} A '''cold finger''' is a piece of laboratory equipment that is used to generate a localized cold surface. It is named for its resemblance to a finger and is a type of...") |
|||
| Line 13: | Line 13: | ||
==Projects== | ==Projects== | ||
| − | *Sublimation | + | *Sublimation of compounds |
*Purify air-sensitive compounds | *Purify air-sensitive compounds | ||
Latest revision as of 14:58, 7 June 2018
 |
This article is a stub. Please help Sciencemadness Wiki by expanding it, adding pictures, and improving existing text.
|
A cold finger is a piece of laboratory equipment that is used to generate a localized cold surface. It is named for its resemblance to a finger and is a type of cold trap.
Contents
Description
The device consists of an elongated chamber where a coolant lowers the temperature of the glass item. There are two models:
- First model uses a continuous stream of cooling fluid, such as cold tap water, or something colder
- Another model is a simple glass tube where a cold material, such as dry ice or dry ice/acetone is added
Cold fingers have a ground glass joint, which allows them to be fitted to a specially designed vacuum flask, which is then connected to a LN2 trap and a vacuum pump.
Availability
Cold fingers can be purchased from lab suppliers. Good quality cold fingers are a bit pricey, but since you need good quality glassware when working under vacuum, it's a good idea to avoid using cheap types and go for something better.
Projects
- Sublimation of compounds
- Purify air-sensitive compounds
