cryophorus
Date: 1870-1920
Inventory Number: 4272
Classification: Experiment
Subject:
Maker: American ?
Cultural Region:
Dimensions:
41.3 x 9.3 x 6.5 cm (16 1/4 x 3 11/16 x 2 9/16 in.)
Material:
Bibliography:
An Explanatory Dictionary of the Apparatus and Instuments Employed in the Various Operations of Philosophical and Experimental Chemistry
Description:
Two glass balls, one with a pointed tip, the other entirely spherical, connected by a J-shaped glass tube. The spherical ball has a crack and the liquid that it used to contain has dried inside leaving white stains.
Signedunsigned
FunctionThis device is used to demonstrate the drop in temperature produced by evaporation.
One ball contains water while the other is empty. The vessel has had its air evacuated so it only has water vapor inside. If the empty ball is immersed in a very cold substance, the water vapor will condense there, reducing the pressure inside the vessel. This pressure drop will induce the evaporation of the water in the other bulb. This evaporation will bring the water temperature down, until it starts to freeze.
One ball contains water while the other is empty. The vessel has had its air evacuated so it only has water vapor inside. If the empty ball is immersed in a very cold substance, the water vapor will condense there, reducing the pressure inside the vessel. This pressure drop will induce the evaporation of the water in the other bulb. This evaporation will bring the water temperature down, until it starts to freeze.