Hot Solvent Dissolution
Hot Solvent Dissolution - Related Videos
10:13
Working with Hot and Cold Sources
0 Views •
2023
Source: Robert M. Rioux & Suprita Jharimune, Pennsylvania State University, University Park, PA Working with extreme temperatures, both high and low, is an integral part of many laboratory operations. For many, mentioning a laboratory instantly evokes the mental picture of a Bunsen burner. Bunsen burners and hot plates are used extensively in small and large operations in research laboratories and industries, thus making it necessary for all users to be aware of their safe handling...
01:12
Solvents
0 Views •
2019
A solvent is a substance, most often a liquid, that can dissolve other substances. Here, the substance being dissolved is called a solute. When a solvent and a solute combine, they form a solution - a homogenous mixture of both the solvent and the solute. Water is a universal biological solvent. Its polar structure allows it to dissolve many other polar compounds. The ability of water to dissolve is governed by a balance between water molecules binding to each other and binding to the solute. A...
09:17
Hot Wire Anemometry
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2023
Source: Ricardo Mejia-Alvarez and Hussam Hikmat Jabbar, Department of Mechanical Engineering, Michigan State University, East Lansing, MI Hot-wire anemometers have a very short time-response, which makes them ideal to measure rapidly fluctuating phenomena such as turbulent flows. The purpose of this experiment is to demonstrate the use of hot-wire anemometry.
06:43
Rotary Evaporation to Remove Solvent
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2023
Source: Dr. Melanie Pribisko Yen and Grace Tang — California Institute of Technology Rotary evaporation is a technique most commonly used in organic chemistry to remove a solvent from a higher-boiling point compound of interest. The rotary evaporator, or "rotovap", was invented in 1950 by the chemist Lyman C. Craig. The primary use of a rotovap is to dry and purify samples for downstream applications. Its speed and ability to handle large volumes of solvent make rotary evaporation a preferred...
09:41
Schlenk Lines Transfer of Solvents
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2023
Source: Hsin-Chun Chiu and Tyler J. Morin, laboratory of Dr. Ian Tonks—University of Minnesota Twin Cities Schlenk lines and high vacuum lines are both used to exclude moisture and oxygen from reactions by running reactions under a slight overpressure of inert gas (usually N2 or Ar) or under vacuum. Vacuum transfer has been developed as a method separate solvents (other volatile reagents) from drying agents (or other nonvolatile agents) and dispense them to reaction or storage vessels while...
FAQs
Heating increases molecular motion within both the solvent and the solid. This greater movement can help solvent molecules contact and penetrate the solid more effectively, while stronger solvent–solute interactions separate particles from the material. The result is improved dissolution for substances that dissolve poorly at room temperature, making subsequent preparation, purification, or analysis more efficient.
The solvent must interact sufficiently with the solid when heated to promote dissolution, while also supporting the intended outcome during cooling. An unsuitable solvent may dissolve too little material or fail to support controlled crystallization. Choosing appropriately therefore affects how completely the sample dissolves and how effectively the dissolved substance can later be purified or recovered.
Controlled cooling can encourage the dissolved material to crystallize after the solid has been dissolved at elevated temperature. As conditions change, the material may become less soluble and separate from the solvent in a more organized form. This makes cooling an important part of recrystallization, linking the initial dissolution step to purification of the recovered substance.
The elevated temperature provides an advantage when room-temperature solvent cannot dissolve enough of a solid for the intended task. Increased molecular motion and improved solvent access can accelerate or enhance separation of particles. However, the heated approach requires deliberate temperature control and attention to solvent flammability, whereas room-temperature dissolution generally involves fewer heating-related safety concerns.
A typical sequence begins by selecting a suitable solvent and combining it with the solid sample. The mixture is then heated under controlled conditions to improve dissolution. Once the material has dissolved, the solution may be cooled in a controlled manner when crystallization is desired. The exact handling depends on whether the goal is preparation, extraction, reaction setup, or purification.
Temperature must be controlled carefully because heating changes both dissolution behavior and laboratory risk. Solvent flammability is especially important when an elevated temperature is required, so the procedure should account for the solvent’s behavior during heating. Careful control helps prevent unsafe operation while also maintaining the conditions needed for consistent dissolution and, when applicable, crystallization.
This technique is useful for recrystallization, extraction, reaction preparation, and analysis of substances that dissolve poorly at room temperature. In recrystallization, heating helps place material into solution before cooling promotes crystallization. For preparation or analysis, improved dissolution can produce a more workable sample. Its value therefore depends on matching solvent choice and temperature control to the experimental objective.