Using a Bunsen burner to heat organic materials in the lab poses a fire risk. Organic materials contain some carbon atoms that make them highly flammable. That means organic materials can catch on fire and sustain combustion. The main reason why you should not use Bunsen burners for organics.
In this article, I first define organic materials and explain why you should not use Bunsen burners to heat them. I also provide safety guidelines, alternatives to Bunsen burners, and specific Bunsen burner organic chemistry risks.
What Are Organic Materials?
An organic molecule has one or more carbon atoms. However, scientists emphasize that an organic molecule must have one other element besides carbon, including sulfur, oxygen, nitrogen, and hydrogen.
Plastics, medicines, and perfumes are examples of artificial organic materials. Crude oil and natural gas comprise hydrocarbons, hydrogen, and carbon compounds.
However, not all molecules with a structure made up of carbon are organic. Some are inorganic, such as carbon dioxide (CO2). Although made entirely of carbons, diamonds, and graphene are still not considered organic materials.
The table below highlights the differences between organic and inorganic materials.
Organic Materials | Inorganic Materials |
---|---|
Carbon atoms give these substances their distinctive properties. | Although there are rare exceptions, most lack carbon atoms. |
More volatile and highly flammable. | Nonvolatile and not flammable. |
Available in liquid, gaseous, and solid forms. | Mostly solid in structure. |
Water insoluble. | Insoluble in some organic solvents, yet soluble in water. |
The rate of reaction is slow. | Have a high rate of reaction. |
Sugars, nucleic acids, hydrocarbon fuels, enzymes, proteins, and lipids are a few examples. | Bases, metals, non-metals, acids, and any compounds set up from a single element are a few examples. |
They are often poor conductors of heat and electricity in aqueous solutions. | They are well known for being good heat and electricity conductors in aqueous solutions. |
Why Not To Use Bunsen Burners for Organics?
Most organic materials in labs are flammable and rapidly burn when close to an open flame. Bunsen burners use natural gases like methane or butane to produce a single gas flame.
The Bunsen burner’s heat quickly brings organic materials to a boil, and evaporation occurs. The vapor can easily catch fire because of the burner’s open flame, causing an explosion.
When heating materials, the glass beakers usually are open. As a result, there will be spills and splashes when the organic ingredients boil. The contact between the spilling compounds and the burner flames frequently causes explosions and fires.
Safety Guidelines For Heating Organic Substances
Many organic substances are flammable. The organic compounds easily ignite in the presence of sparks and flames, which might ultimately result in a fire or an explosion.
However, following the recommendations below, lab safety with organic heating is possible.
- When working with organic materials, you must be in a well-ventilated space. Work in the fume hood to keep chemical fumes out of your lungs. It’s important to remember that most organic compounds are harmful and carcinogenic.
- Properly dispose of waste organic materials. Due to their incompatibility, some combinations of organic and inorganic compounds might result in severe reactions. As a result, put all organic trash in containers with the appropriate labels. Keep organic trash out of the sink.
- Avoid using Bunsen burners when heating organic materials since they can catch fire at high temperatures, even without open flames.
- Confirm that the glass beakers you use have no cracks to avoid shattering when heated. The cracked glass will have tiny gaps, allowing organic vapors to escape and cause a fire.
- You should never leave a hot plate or burner unattended.
- Avoid keeping anything flammable on the bench where you are using a Bunsen burner.
- The location of the nearest exit, safety equipment, and fire extinguishers should all be known to you.
Alternatives To Bunsen Burners For Organics
Bunsen burners are not ideal due to the open flames they produce when heating high-volatile organic materials. Accordingly, I advise using Bunsen burner alternatives.
Electric Hot Plate
Small (individual) and large (communal) hot plates are the two sizes of the plates. The smaller plates are in the cabinets under the fume hoods. Larger hot plates are within or next to fume hoods.
Most hot plates have coverage against sparks. Hot plates are suitable when heating substances with boiling points above 212°F (100°C). The hot plates are far safer than open flame heaters like gas burners.
Hot plates are safe when plugged into a circuit protected by ground-fault circuit interrupters (GFCI). The circuit protects you from electrocution caused by spills or an exposed wire.
In their YouTube channel, the University of California, Berkeley demonstrates the proper use of a fume hood.
Water (Steam) Baths
Steam baths are primarily found underneath the fume hoods. They connect to the benches’ or fume hoods’ steam outlets (steam enters through the upper connection).
Place a beaker of water on a hot plate. Place a second beaker containing the organic materials you want to work in the first beaker’s water bath. The organic material receives heat transfer from the water bath.
Securely place the exit pipe, which drains the water when it condenses in a sink or drain. The exit pipe is always lower than the entrance pipe. You can take off the metal rings to accommodate flasks of all sizes.
Steam baths only reach a temperature of 212°F (100°C). Therefore, using a steam bath, you can only distill liquids with boiling temperatures of 176°F (80°C) or lower.
On their YouTube channel, Flinn Scientific Inc., the supplier of science supplies and equipment, provides instructions on how to set up a water bath.
Electric Heating Mantles
An electric heating mantle is a device that converts electric current into heat energy. They are excellent alternatives to Bunsen burners for organics. Most electric heating mantles have controller devices to regulate uniform heat distribution when using round-bottomed glass beakers.
There are two different designs available for electrical heating mantles with control mechanisms.
- A single unit with an integrated controller and a mantle.
- A separate mantle and controller, which you buy together.
Most electric heating mantles have a specific design; you can only use them with beakers or vessels with straight sides. There are, however, mantles with flexible and soft-sided chamber linings. Round-bottomed beakers and other glassware with irregular shapes can fit on these mantles.
Bunsen Burner Organic Chemistry Risks
Organic chemistry risks are critical hazards due to the dangerous properties of the chemicals found in the lab. Not handling organic materials safely can cause physical damage to you or your property or lead to health problems.
Eruption And Spread Of Fire
The explosion and spread of fire is one of the main dangers. When you light a Bunsen burner in the lab, the presence of organic substances presents the greatest risk. The flash points of most organic compounds are incredibly low. Any substance that has a flash point lower than 59°F (15°C) tends to be highly flammable.
The table below lists some of the organic materials’ flash points.
Organic Materials Flash Point | |
---|---|
Ethanol = 53.6°F (12°C). | Pentane = -56.2°F (-49°C). |
Methanol = 44.6°F (7°C). | Toluene = 39.2°F (4°C). |
Acetonitrile = 42.8°F (6°C). | Hexane = -9.4°F (23°C). |
1,4-dioxane = 53.6°F (12°C). | Diethyl ether = -49°F (-45°C). |
Ethyl acetate = 24.08°F (-4.4°C). | Tetrahydrofuran = 1.4°F (-17°C). |
Carbon disulfide = -22°F (-30°C). | Acetone = -0.4°F (-18°C). |
Solution: Cover the fire with a wire mesh, dry ice, or sand if it is in a tiny glass container. If the fire is in a big glass container or has spread, dry ice or a dry chemical extinguisher will work better. You should not use a carbon dioxide extinguisher since it might trigger the fire to spread. You should not use water to extinguish the fire because water flows, spreading the fire.
Burns
Another chemical risk is getting burns from a Bunsen burner. You will get burnt when the heat from the burner comes into contact with your skin. Temperatures above 158°F (70°C ) are hazardous.
Solution: Maintain a safe distance from lit bunsen burners. Avoid heat sources near organic materials, clothing, and safety equipment known to be quite explosive. Don’t leave the Bunsen burners unattended.
Inhaling Hazardous Vapors
When heated, most organic materials release dangerous fumes and gasses. Inhaling these dangerous compounds might have short- or long-term negative health impacts.
When you come into contact with the substances, you begin to feel their short-term effects. The effects that persist long after the initial exposure are known as long-term effects.
Solution: Using the fume hood correctly will protect you from lab chemical inhalation. Use dust masks and respirators if the fume hoods are not available.
Conclusions
Using a Bunsen burner with organic materials would be dangerous because they are highly flammable. However, safer alternatives are available, such as electric heating mantles, hot plates, and steam baths.
Bunsen burner organic chemistry risks include breathing in potentially harmful gases, getting burned, and having a fire start and spread.
Frequently Asked Questions
1. Can I use a Bunsen burner in organic chemistry?
No, I would recommend you use alternatives to Bunsen burners for organics. This is mainly because organic materials have carbon atoms, making them highly volatile and flammable.
Instead of the Bunsen burners, you can use steam baths, hot plates, and hot mantles.
2. What are some safety measures when heating organic substances?
Due to flammability concerns, following some safety guidelines for heating organic substances is the most important. The first is to avoid using an open flame when healing the organic substances.
Wear protective clothing such as splash goggles or safety glasses, a flame-resistant lab coat, and insulating heat-resistant gloves.
Always know the location of fire extinguishers in case of any eventualities.
Raoul Lobo is a seasoned expert in the realm of home appliances and environmental comfort. As a prominent author at TemperatureMaster.com, Raoul’s passion and expertise shine through in his insightful articles and guides. With years of hands-on experience, he has become a trusted source for readers seeking advice on pools, washers, dryers, and a wide range of other appliances.