Distilling Mercury Metal

NileRed
26 Nov 201619:53
EducationalLearning
32 Likes 10 Comments

TLDRThe video script details a meticulous process of distilling mercury to achieve high purity. The presenter begins with a caution about the dangers of mercury exposure and emphasizes the importance of safety precautions. The mercury, sourced from two separate batches, is first cleaned mechanically and chemically before the distillation process. The distillation setup includes a heating mantle, an air condenser, and a vacuum pump to lower the boiling point of mercury. The presenter uses a beaker filled with water to prevent mercury vapor release and employs a syringe to remove excess water. Throughout the process, the presenter discusses the challenges and observations, such as the self-sealing nature of the mercury under vacuum and the reflective surface it creates. The distilled mercury is collected in a flask, and the setup is carefully dismantled for cleaning. The final yield is measured, and the results are compared to the initial estimate. The video concludes with a teaser for upcoming content on dibenzylacetone and a thank you to supporters on Patreon.

Takeaways
  • 🧪 The process of distilling mercury involves two major steps: mechanical and chemical cleaning followed by distillation.
  • ⚠️ Cleaning mercury is dangerous, with the distillation step posing a higher risk due to the generation of mercury vapor.
  • 💧 A layer of water above the mercury is used to suppress mercury vapor release, which is harmful if inhaled.
  • 🔥 Mercury boils at a high temperature, which can risk breaking glassware and releasing a large amount of mercury vapor.
  • 🔬 The speaker used a vacuum distillation method to lower the boiling point of mercury from 360ºC to around 260ºC.
  • 🧴 The use of grease to seal joints was not possible due to its low temperature tolerance, so the setup self-sealed as mercury boiled.
  • 🧴 A trap was used in the vacuum distillation setup to prevent mercury from reaching and damaging the vacuum pump.
  • 🔍 The distillation process was carefully monitored to avoid reaching dryness, which could be dangerous.
  • 🧵 Mercury has a high surface tension, which causes it to form distinct beads on glass and travel as separate drops.
  • 📐 The final volume of clean mercury obtained was 292.5 ml, and the dirty mercury with glass was about 46 ml.
  • 📈 The speaker's next video will be on dibenzylacetone, based on community poll results and Patreon feedback.
Q & A
  • What are the two major steps involved in distilling mercury?

    -The two major steps involved in distilling mercury are mechanical and chemical cleaning, and distillation. The cleaning step is crucial as it removes most of the contaminants before the actual distillation process.

  • Why is it important to work over containers when handling mercury?

    -Working over containers is important to catch any possible spills of mercury, which is hazardous. Spills can release harmful mercury vapors into the air and pose a significant health risk.

  • Why is an air condenser used instead of a water condenser for mercury distillation?

    -An air condenser is used because mercury boils at a high temperature. Using a water condenser could cause the water to boil if it doesn't pass fast enough, creating a large temperature differential that might crack the glassware.

  • What is the role of the trap in the distillation setup?

    -The trap serves as an intermediate between the vacuum pump and the distillation apparatus. It prevents any mercury from reaching and potentially damaging the pump.

  • Why is it not recommended to distill mercury to dryness?

    -Distilling mercury to dryness is not recommended because it can leave behind impurities and broken glass, which could contaminate the mercury and pose a safety hazard.

  • How is the vacuum distillation of mercury different from distillation under normal atmospheric pressure?

    -Vacuum distillation allows mercury to boil at a lower temperature, around 260ºC compared to its normal boiling point of 360ºC. This reduces the risk of damage to the glassware and makes the process safer.

  • What is the purpose of adding broken glass to the distillation flask?

    -The broken glass is added to help with the boiling process. Although mercury has a high density and the glass just sits on top, it is believed that the broken glass might aid in the distillation process, possibly by increasing surface area for boiling.

  • Why does the distiller cover the 1-liter flask with aluminum foil?

    -The aluminum foil is used to insulate the flask, which helps the mercury vapor to condense more efficiently and prevents heat loss, ensuring a smoother distillation process.

  • What is the reason for using an isopropanol dry ice bath?

    -The isopropanol dry ice bath is used to cool the trap during the distillation process. It helps to condense the mercury vapor, preventing it from reaching the vacuum pump and ensuring a cleaner distillation.

  • Why is it necessary to cap the receiving flask when removing the vacuum adapter?

    -Capping the receiving flask prevents any dust, dirt, or other contaminants from falling into the fresh mercury, ensuring the purity of the distilled mercury.

  • How does the distiller ensure the cleanliness of the mercury after the distillation process?

    -The distiller transfers the clean mercury into a thoroughly cleaned storage container, adds a layer of distilled water to minimize vapor release, and uses a wash bottle to clean the funnel to avoid any contamination.

  • What is the significance of the distiller's decision to not distill to dryness and to reserve some mercury with broken glass for future distillation?

    -Not distilling to dryness prevents leaving behind impurities and broken glass, which could contaminate the mercury. Reserving some mercury with broken glass for future distillation allows for further purification in subsequent runs, potentially increasing the overall purity of the mercury.

Outlines
00:00
🧪 Mercury Distillation Setup and Precautions

The video begins with the presenter discussing the process of distilling mercury, emphasizing the importance of prior mechanical and chemical cleaning. They highlight the dangers of mercury fumes and the risk of spills, outlining the safety measures taken, such as working over containers and in a well-ventilated area. The presenter introduces the mercury sources, explains the use of water to suppress mercury vapor, and demonstrates the process of removing water from the mercury before distillation. The setup for the distillation includes a distillation flask, heating mantle, air condenser, and a vacuum pump with a trap to prevent mercury from reaching the pump. The process is carefully explained, with attention to the potential risks of using a water condenser due to the high boiling point of mercury.

05:04
🕹 Vacuum Distillation of Mercury and Challenges

The presenter describes the vacuum distillation process, explaining the benefits of boiling mercury at a lower temperature under vacuum to reduce risks. They discuss the distillation apparatus setup, including the use of a receiving flask and a trap to protect the vacuum pump. The video shows the actual pouring of mercury into the distillation flask and the initial stages of the distillation, where water is removed first. The presenter also addresses the decision not to use a separatory funnel and the reasoning behind it. As the distillation progresses, the presenter encounters and resolves issues with the vacuum seal and boiling violence, demonstrating how the mercury begins to self-seal the joints as it boils. The summary also includes the observation of mercury's reflective properties and its high surface tension as it condenses and collects in the receiving flask.

10:11
🚨 Stopping Violent Boiling and Completing the Distillation

The video captures a moment of intense boiling, which the presenter acknowledges as dangerous and stops by removing the heat source. They then carefully restart the process to avoid a repeat, focusing on achieving a steady distillation. The presenter discusses the appearance of mercury vapor, its invisible nature, and how it condenses on the glass. They also mention the use of aluminum foil to insulate the flask and increase the distillation rate. The video progresses to show the smooth distillation process, the mesmerizing formation of mercury droplets, and the final stages of the distillation. The presenter decides not to distill to dryness, emphasizing the importance of stopping at the right time. After the distillation, they allow the apparatus to cool before dismantling and cleaning each component, including the vent adapter, air condenser, and vacuum adapter.

15:12
🧼 Post-Distillation Cleanup and Future Plans

After the distillation process, the presenter focuses on the cleanup, ensuring the receiving flask is capped to protect the distilled mercury. They examine the trap and confirm that it didn't catch any mercury, suggesting that the distillation process was effective. The presenter then transfers the clean mercury into a storage container, taking care to avoid spills. They also discuss the cleanup process for the distillation flask and the remaining mercury, including the use of water to wash away any leftover mercury. The presenter concludes with measurements of the distilled mercury, comparing the results with their initial estimates. They provide updates on upcoming videos, including dibenzylacetone and part four of the paracetamol synthesis, and express gratitude to their Patreon supporters. They also encourage viewers to subscribe for the latest videos and to provide suggestions for future content.

Mindmap
Keywords
💡Distillation
Distillation is a process of separating components from a liquid mixture by selective evaporation and condensation, which is a crucial step in the video's narrative. It is used to purify mercury by heating it to its boiling point and condensing the vapor to obtain a purer form. The video demonstrates the distillation process in detail, emphasizing the importance of safety and technique.
💡Mercury
Mercury is a chemical element with the symbol Hg and is a heavy, silvery, toxic liquid at room temperature. It is the main substance being purified in the video. The script discusses the risks associated with mercury, such as its tendency to fume at room temperature and the potential for spills and exposure.
💡Contaminants
Contaminants refer to impurities or unwanted substances that can affect the purity of the mercury. The video emphasizes the importance of removing these contaminants through initial cleaning steps before distillation. Contaminants can include mineral oil, as mentioned in the script, or other substances that may have been mixed with the mercury.
💡Vacuum Distillation
Vacuum distillation is a process where the distillation is performed in a vacuum to lower the boiling point of the substance being distilled. In the context of the video, it is used to boil mercury at a lower temperature of around 260ºC instead of its normal boiling point of 360ºC, making the process safer and more efficient.
💡Surface Tension
Surface tension is a property of liquids that results from the cohesive forces between liquid molecules. Mercury has a very high surface tension, which is demonstrated in the video by the formation of mercury beads on the condenser. This property gives mercury its distinctive behavior, such as forming separate drops and creating a mirror-like surface.
💡Safety Precautions
Safety precautions are measures taken to prevent harm or accidents. The video script highlights various safety measures, such as working over containers to catch spills, using a well-ventilated area, and employing a vacuum distillation setup to minimize the risk of mercury vapor exposure and spills.
💡Boiling Point
The boiling point is the temperature at which a substance changes from a liquid to a gas. Mercury's boiling point is a key factor in the distillation process, and the video discusses how the boiling point is affected by vacuum conditions. The normal boiling point of mercury is around 360ºC, but under vacuum, it can be reduced to approximately 260ºC.
💡Condenser
A condenser is a device used to convert a gas back into a liquid, typically through cooling. In the video, an air condenser is used instead of a water condenser to avoid the risk of cracking due to temperature differentials. The condenser plays a vital role in the distillation process by allowing the mercury vapor to condense and be collected.
💡Vacuum Pump
A vacuum pump is a device that removes gas from a sealed volume to create a vacuum. In the context of the video, the vacuum pump is used to lower the pressure in the distillation apparatus, which facilitates the boiling of mercury at a lower temperature and helps to prevent the escape of mercury vapor into the atmosphere.
💡Density
Density is the mass per unit volume of a substance. The video uses the concept of density to estimate the volume of mercury by dividing the mass of the mercury-containing bottle by the density of mercury. This estimation helps in deciding the appropriate size of the flask for distillation.
💡Oxidation
Oxidation is a chemical reaction that involves the transfer of electrons from one substance to another, often resulting in the degradation of the substance. The script mentions that the mercury on the right had been oxidized and become dirty since it was cleaned in a previous video, indicating the need for further purification through distillation.
Highlights

The process of distilling mercury involves two major steps: mechanical and chemical cleaning followed by distillation.

Mechanical and chemical cleaning is crucial for removing the bulk of contaminants before distillation.

Distillation increases the purity of mercury and is performed mostly for its visual appeal and scientific interest.

Safety measures include working over containers to catch spills and in well-ventilated areas to avoid mercury vapor inhalation.

The risk of cracking glassware during distillation due to mercury's high boiling point is mitigated by using an air condenser instead of a water condenser.

Distillation under vacuum allows for boiling mercury at lower temperatures, reducing the risk of damage to equipment.

A trap is used in the distillation setup to prevent mercury from reaching and damaging the vacuum pump.

The distillation flask should not be filled above halfway to ensure proper boiling during the process.

Mercury's high density allows for the addition of broken glass to the flask without mixing.

Water is initially distilled off before mercury begins to distill, ensuring any mineral oil is also removed.

The use of a cold bath with isopropanol and dry ice is demonstrated for cooling purposes in the distillation process.

Mercury's boiling under vacuum can cause the joints to self-seal, improving the vacuum quality.

Violent boiling can lead to impurities being transferred with the mercury; careful heating is required to avoid this.

Mercury vapor is invisible and beads up immediately upon condensation, demonstrating high surface tension.

The distillation process is monitored closely, with adjustments made to ensure a steady and clean collection of mercury.

Insulation of the adapter helps increase the rate of distillation and improve the mercury's transfer.

The final distillation results in shiny, mirror-like mercury, indicating a high level of purity.

Distillation should not be taken to dryness to prevent potential damage and ensure safety.

Cleanup involves thorough washing of all equipment used in the distillation process to remove any residual mercury.

The distillation process yields approximately 292.5 ml of clean mercury and 46 ml of dirty mercury with some glass.

Transcripts
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