Related Experiment Video
Updated: Jul 12, 2026
13:27
Exploring the Effects of Atmospheric Forcings on Evaporation: Experimental Integration of the Atmospheric Boundary Layer and Shallow Subsurface
Published on: June 8, 2015
Direct Observation of Evaporation from Quiescent Water
Science (New York, N.Y.)
|January 9, 1959
Summary
Cobaltous chloride-impregnated filter paper visually indicates water evaporation rates. This method reveals how monolayers impact thermal convection currents in liquids.
Area of Science:
- Physical Chemistry
- Surface Science
Background:
- Evaporation rate is crucial in various scientific and industrial processes.
- Understanding liquid surface dynamics, including thermal convection, is important for heat and mass transfer studies.
Purpose of the Study:
- To demonstrate a simple visual method for assessing regional evaporation rates from a water surface.
- To show the influence of monolayers on thermal convection currents within a liquid.
Main Methods:
- Utilizing filter paper impregnated with cobaltous chloride as an indicator.
- Observing color changes on the filter paper positioned above the water surface.
- Analyzing the visual data to infer evaporation patterns and convection effects.
Main Results:
- The color change of the cobaltous chloride paper provided a clear indication of varying evaporation rates across the water surface.
- The presence of certain monolayers demonstrably altered thermal convection currents, as evidenced by the evaporation patterns.
Conclusions:
- Cobaltous chloride-impregnated filter paper is an effective and accessible tool for visualizing evaporation dynamics.
- Monolayers can significantly influence thermal convection, impacting the overall evaporation process.
Related Concept Videos
01:10Volatilization
Volatilization gravimetry is an analytical technique that measures the mass lost due to the volatilization of the substance. This technique is used to estimate the amount of volatile material in a sample. To perform this method, heat a known amount of the sample to a high temperature in a crucible or other suitable vessel. The volatile substance in the sample evaporates, and the vapor is completely expelled from the crucible either by heating the sample or bubbling a stream of inert gas through...
01:18Vaporization
The physical form of a substance changes by changing its temperature. For example, raising the temperature of a liquid causes the liquid to vaporize (convert into vapor). The process is called vaporization—a surface phenomenon. For vaporization to occur, kinetic energy must be greater than the intermolecular forces that keep molecules bonded. The amount of energy needed to vaporize a quantity of liquid at a given pressure and a constant temperature is called the heat of vaporization. When...
02:39Phase Transitions: Vaporization and Condensation
The physical form of a substance changes on changing its temperature. For example, raising the temperature of a liquid causes the liquid to vaporize (convert into vapor). The process is called vaporization—a surface phenomenon. Vaporization occurs when the thermal motion of the molecules overcome the intermolecular forces, and the molecules (at the surface) escape into the gaseous state. When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase molecules...
01:19Precipitation Titration: Endpoint Detection Methods
In argentometric precipitation titrations, endpoints can be detected visually by the Mohr, Volhard, and Fajans methods. In the Mohr method, adding a soluble chromate indicator gives an initial yellow color to the analyte solution. As the titrant is added, the first excess of silver ions forms a red silver chromate precipitate, marking the endpoint. The solution pH should be maintained at about 8 by adding solid CaCO3.
In the Volhard method, a standard excess of AgNO3 is first added to the...
In the Volhard method, a standard excess of AgNO3 is first added to the...
00:52Washing, Drying, and Ignition of Precipitates
After filtration, the precipitate is washed to remove coprecipitated impurities and any remaining mother liquor. Colloidal precipitates, such as silver chloride, are washed with an electrolyte (such as dilute nitric acid) to prevent the peptization of the precipitate. In the case of slightly soluble precipitates, the wash solution contains a common ion to reduce solubility. Lead sulfate, which is slightly soluble in water, is washed with dilute sulfuric acid. Similarly, wash solutions may be...
01:01Distillation: Vapor–Liquid Equilibria
Distillation is a separation technique that takes advantage of the boiling point properties of disparate elements in a mixture. To perform distillation, we begin by heating a miscible mixture of two liquids with a significant difference in boiling points (at least 20°C). As the solution heats up and reaches the bubble point of the more volatile component, some molecules of the more volatile component transition into the gas phase and travel upward into the condenser, which is a glass tube with...