Simple Science - Experiment Digest # 36
I continue to publish our digests “Simple Science”. By the way, today is the 36th issue in three years.
In today's issue:
- a light bulb in liquid nitrogen;
- chemical focus with a scarf;
- water curvature;
- quantum levitation.
Liquid nitrogen lamp
ATTENTION: breaking a glass flask, we exposed the contacts to which the current 220v was applied. This stress is life threatening!
The experiment clearly shows how an open spiral of an incandescent lamp quickly burns out in air and remains unharmed when immersed in liquid nitrogen. It can be concluded: nitrogen is not an oxidizing agent and does not conduct electric current in liquid form.
During the production of incandescent lamps, for example, the one that we broke before conducting the experiment, they are filled with inert gas. One of these gases is argon, and sometimes nitrogen.
Chemical trick with a scarf
The experience is based on the formation and destruction of crystalline hydrates of compounds. Demonstrates discoloration of compounds when water is added or removed. Initially, the cobalt chloride solution is pink. When heated, water from the surface of the scarf evaporates and cobalt chloride precipitates in the form of a pink crystalline hydrate. Further heating leads to the destruction of the aquatic complex. So at temperatures above 110 degrees Celsius, the compound turns into anhydrous CoCl2 having a blue color. As soon as we add water again, water is built into the crystal lattice, crystalline hydrate is formed again and the scarf becomes pink again.
In the video, there was an inaccuracy in the dubbing: the curvature of the jet can be seen directly on the camera, but only this camera should have an adjustable shutter speed (tent), which should be as low as possible and conduct the experiment either on the street on a sunny day, or use additional lighting devices. But not all cameras have such a function, especially amateur cameras. Our goal was to show how this can be done even at home. For example, there are cameras that shoot at a frequency of 240 frames / second, and the iPhone 6 already has the ability to shoot it.
I remind you of our books to those who have not yet had time to buy a gift for their child or nephew for the new year.