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Safety flame
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∙ 11y ago
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Why should a lit Bunsen burner never be left unattended?
It is dangerous as other people may just place their hand or other objects over the Bunsen burner causing injuries or burns, especially if it is a non-luminous flame which makes it difficult to tell that the burner is actually lit. You should always switch off the Bunsen burner before leaving to prevent injuries to others and yourself.
How does a yellow flame on a Bunsen burner make things black but the roaring flame doesn't?
The flame of a Bunsen burner that is yellow in color will leave a black carbon residue due to the incorrect mixture of oxygen into the flame. Because there is not enough oxygen for complete combustion, the carbon reside is left behind. When the Bunsen flame has a sufficient amount of oxygen mixed in, hence the 'roaring flame', it has a blue color and does not leave a carbon residue due to complete combustion of the acetylene gas.
What is the difference between the 3 different flames on a Bunsen burner?
The different flames are a) the luminous flame b) the blue flame c) the roaring flame The luminous flame is for safety and when the burner is not in use, should be left on it because you can see the flame becuase it is yellow. The hole must be closed for the luminous flame. The blue flame is generally used for expirements and is slightly weaker than the roaring flame. It can be gotten through opening the nole half-way. The roaring flame is only used in expirements when you need extra-strength becuase it is the hottest and most powerful flame. It is achevied through a fully opened hole.
What is the name of the black solid which collects on the outside of an evaporating basin when it is heated by a yellow Bunsen flame?
The black solid left is whatever is left of the compound or elements. This is most likely the leftover water.
What does the yellow gas flame means?
If you are burning natural gas, it means that the burner is dirty and not getting anough air. If left untreated it will lead to sooting and possibly carbon monoxide problems. Get the burner serviced immediately. If you are burning propane gas, there will be a yellow "tip" to the flame, this is a normal condition. The flame should not be all yellow however, this indicates the same problem as with natural gas.
Why should a lit Bunsen burner never be left unattended?
It is dangerous as other people may just place their hand or other objects over the Bunsen burner causing injuries or burns, especially if it is a non-luminous flame which makes it difficult to tell that the burner is actually lit. You should always switch off the Bunsen burner before leaving to prevent injuries to others and yourself.
How does a yellow flame on a Bunsen burner make things black but the roaring flame doesn't?
The flame of a Bunsen burner that is yellow in color will leave a black carbon residue due to the incorrect mixture of oxygen into the flame. Because there is not enough oxygen for complete combustion, the carbon reside is left behind. When the Bunsen flame has a sufficient amount of oxygen mixed in, hence the 'roaring flame', it has a blue color and does not leave a carbon residue due to complete combustion of the acetylene gas.
What safety precautions should you take when using a Bunsen burner?
Bunsen burners are a fire hazard and should not be left unattended. However, accidents can occur even when the burner is off. Check the tubing connecting the gas line to the burner to be certain there are no cracks and it is secure. If the tubing is dislodged and the gas line valve is not off, gas will fill the room creating a potential explosion situation. This has happened. There are safer alternatives to the classic Bunsen burner. A Flame Boy or a Touch-o-matic burner eliminates the issue of a constant flame. A bacticinerator can be used to sterilize plating loops. There are also glass bead sterilizers that may be used.
What is a regular flame on a Bunsen burner?
I am not 100% sure what you are asking here however I will do my best to answer it. The gas that is used in most bunsen burners is methane (natural gas). This is not true for all labs as I have heard of labs using town gas (which is made from distillation of coal). A regular flame on a bunsen is orange this the coolest flame (300°C) and is rarely used. more common will be the blue flame which closer to 700°C. When leaving the bunsen for any length of time the orange flame should be left on as it is easy to observe and insures the safety of your fellow class mates.
What is a regular flame on the Bunsen burner?
I am not 100% sure what you are asking here however I will do my best to answer it. The gas that is used in most bunsen burners is methane (natural gas). This is not true for all labs as I have heard of labs using town gas (which is made from distillation of coal). A regular flame on a bunsen is orange this the coolest flame (300°C) and is rarely used. more common will be the blue flame which closer to 700°C. When leaving the bunsen for any length of time the orange flame should be left on as it is easy to observe and insures the safety of your fellow class mates.
What is the difference between the 3 different flames on a Bunsen burner?
The different flames are a) the luminous flame b) the blue flame c) the roaring flame The luminous flame is for safety and when the burner is not in use, should be left on it because you can see the flame becuase it is yellow. The hole must be closed for the luminous flame. The blue flame is generally used for expirements and is slightly weaker than the roaring flame. It can be gotten through opening the nole half-way. The roaring flame is only used in expirements when you need extra-strength becuase it is the hottest and most powerful flame. It is achevied through a fully opened hole.
Why are people recommended to use a blue flame on a Bunsen burner to heat a substance rather than the yellow flame?
The blue flame is hotter. It also burns more efficiently, producing less soot, so you don't get black marks on vessels left in the flame for a long time. The yellow "safety" flame should be used when not heating something as it is cooler and more visible, so you're less likely to accidentally burn yourself.
What is a wing top or flame spreader and how is it used?
A wing top is an accessory that can be used with a Bunsen burner to provide a broad flat fan flame, similar to that of a fishtail burner. It is often used to bend glass as it spread out the heat over a larger area, making it more uniform.See the Web Links to the left for a picture.
What is a Bunsen burner and what is it's uses?
From Wikipedia (see Link to the left):A Bunsen burner is a device used in scientific laboratories for heating, sterilization, and many other uses.The device safely burns a continuous stream of a flammable gas such as natural gas (which is principally methane) or a liquified petroleum gas such as propane, butane, or a mixture of both.From ScienceByJones.com (see Link to the left):The Bunsen burner is used frequently in the laboratory as a source of heat. This burner is designed so that gaseous fuel may be mixed with the correct amount of air to yield the maximum amount of heat. In order to use this burner properly and safely, it is essential that you understand its construction and the adjustments that can be made.The three principal parts of the burner are: barrel, needle valve, and base. The quantity of gas admitted to the burner is controlled by the needle valve, while the air needed for combustion is admitted at the small opening around the bottom of the barrel. The air is controlled by turning the barrel so as to make the air holes larger or smaller.Always open the desk outlet valve fully and regulate the gas supply to the burner by the needle valve. Always extinguish your burner by turning off the desk outlet valve (and then closing the needle valve and barrel.) If there is an accident always shut off the desk outlet valve immediately.STEPS TO LIGHT BUNSEN BURNER:1. Check connections to burner and desk outlet valve.2. Close needle valve and barrel.3. Open desk outlet valve fully.4. Check for leaks with flame.5. While holding flame above barrel, open needle valve 1/2 turn.6. Adjust barrel and needle valve for blue in blue flame.Always light burner in open space on lab counter. After you have adjusted it for the flame needed move it into position. One person in lab group is always responsible for maintaining the burner and flame.Burner Procedure:1. Light the burner according to our rules. Observe the yellow flame which is produced because not enough air is admitted to give complete combustion. The yellow color is caused by small particles of unburned carbon which become incandescent.2. Now rotate the barrel until the flame is entirely blue. Two different zones should appear when the burner is correctly adjusted. Too much air should not be admitted as it may cool the flame or blow it out entirely. After having the teacher confirm a good hot, blue flame draw a diagram of the flame (use labels and descriptions). Indicate on your diagram of the flame where the hottest part of the flame is located.See the Web Links to the left for more information.Bunsen burner barrels can be rotated, either opening or closing the barrel, to adjust the flow of air or oxygen, thereby controlling the flame.
How does the number of carbon atoms affect the degree of luminosity of the flame produced?
luminous flame is the flame when you have not opened the air hole of your Bunsen burner. it moves around a lot. it looks a bit like the flame you find on candles. only it's a lot bigger. non-luminous flame is the flame when you have opened the air holes of your Bunsen burner. it's really steady, coloured blue only with no orange around it. sometimes though, you'll see small orange flames going up and disappears. ---------------------------------------------- Luminous: emitting light A luminous flame is created from an exothermic reaction (normally oxidisation) between that also emits visible light (EM radiation of wavelength 390[violet light]-750nm[red light]). A non-luminous flame is one that doesn't (EM radiation of wavelength<390nm but >750nm) Basically, if a reaction is making lots of heat (your normal, yellow Bunsen burner flame is at about 700^C) and you can see it, it's luminous. If you can't see it (and the heat is there) then it's non-luminous) [The yellow Bunsen burner flame is from the oxidisation of carbon molecules left over from the methane-oxygen reaction. The blue one is too, it's just happening faster so the wavelength decreases - ask your local physics teacher or put 100nm into Wikipedia search]
What is a Bunsen burner and its parts and how is it used?
From Wikipedia (see Link to the left):A Bunsen burner is a device used in scientific laboratories for heating, sterilization, and many other uses.The device safely burns a continuous stream of a flammable gas such as natural gas (which is principally methane) or a liquified petroleum gas such as propane, butane, or a mixture of both.From ScienceByJones.com (see Link to the left):The Bunsen burner is used frequently in the laboratory as a source of heat. This burner is designed so that gaseous fuel may be mixed with the correct amount of air to yield the maximum amount of heat. In order to use this burner properly and safely, it is essential that you understand its construction and the adjustments that can be made.The three principal parts of the burner are: barrel, needle valve, and base. The quantity of gas admitted to the burner is controlled by the needle valve, while the air needed for combustion is admitted at the small opening around the bottom of the barrel. The air is controlled by turning the barrel so as to make the air holes larger or smaller.Always open the desk outlet valve fully and regulate the gas supply to the burner by the needle valve. Always extinguish your burner by turning off the desk outlet valve (and then closing the needle valve and barrel.) If there is an accident always shut off the desk outlet valve immediately.STEPS TO LIGHT BUNSEN BURNER:1. Check connections to burner and desk outlet valve.2. Close needle valve and barrel.3. Open desk outlet valve fully.4. Check for leaks with flame.5. While holding flame above barrel, open needle valve 1/2 turn.6. Adjust barrel and needle valve for blue in blue flame.Always light burner in open space on lab counter. After you have adjusted it for the flame needed move it into position. One person in lab group is always responsible for maintaining the burner and flame.Burner Procedure:1. Light the burner according to our rules. Observe the yellow flame which is produced because not enough air is admitted to give complete combustion. The yellow color is caused by small particles of unburned carbon which become incandescent.2. Now rotate the barrel until the flame is entirely blue. Two different zones should appear when the burner is correctly adjusted. Too much air should not be admitted as it may cool the flame or blow it out entirely. After having the teacher confirm a good hot, blue flame draw a diagram of the flame (use labels and descriptions). Indicate on your diagram of the flame where the hottest part of the flame is located.See the Web Links to the left for more information.Bunsen burner barrels can be rotated, either opening or closing the barrel, to adjust the flow of air or oxygen, thereby controlling the flame.
What is Bunsen burner and how it is used?
When the University of Heidelberg hired Robert Bunsen in 1852, the authorities promised to build him a new laboratory building. Heidelberg had just begun to install coal-gas street lighting, so the new laboratory building was also supplied with illuminating gas. Illumination was one thing; a source of heat for chemical operations something quite different. Previous laboratory lamps left much to be desired regarding economy and simplicity, as well as the quality of the flame; for a burner lamp, it was desirable to maximize the temperature and minimize the luminosity. While his building was still under construction late in 1854, Bunsen suggested certain design principles to the university's talented mechanic, Peter Desaga, and asked him to construct a prototype. The Bunsen/Desaga design succeeded in generating a hot, sootless, non-luminous flame by mixing the gas with air in a controlled fashion before combustion. Desaga created slits for air at the bottom of the cylindrical burner, the flame igniting at the top. By the time the building opened early in 1855, Desaga had made fifty of the burners for Bunsen's students. Bunsen published a description two years later, and many of his colleagues soon adopted the design. The device in use today safely burns a continuous stream of a flammable gas such as natural gas (which is principally methane) or a liquefied petroleum gas such as propane, butane, or a mixture of both. The burner has a weighted base with a connector for a gas line (hose barb) and a vertical tube (barrel) rising from it. The hose barb is connected to a gas nozzle on the lab bench with rubber tubing. Most lab benches are equipped with multiple gas nozzles connected to a central gas source, as well as vacuum, nitrogen, and steam nozzles. The gas then flows up through the base through a small hole at the bottom of the barrel and is directed upward. There are open slots in the side of the tube bottom to admit air into the stream via the Venturi effect, and the gas burns at the top of the tube once ignited by a flame or spark. The most common methods of lighting the burner are using a match or a spark lighter. The amount of air (or rather oxygen) mixed with the gas stream affects the completeness of the combustion reaction. Less air yields an incomplete and thus cooler reaction, while a gas stream well mixed with air provides oxygen in an equimolar amount and thus a complete and hotter reaction. The air flow can be controlled by opening or closing the slot openings at the base of the barrel, similar in function to a car's carburetor. If the collar at the bottom of the tube is adjusted so more air can mix with the gas before combustion, the flame will burn hotter, appearing blue as a result. If the holes are closed, the gas will only mix with ambient air at the point of combustion, that is, only after it has exited the tube at the top. This reduced mixing produces an incomplete reaction, producing a cooler but brighter yellow which is often called the "safety flame"or "luminous flame". The yellow flame is luminous due to small soot particles in the flame which are heated to incandescence. The yellow flame is considered "dirty" because it leaves a layer of carbon on whatever it is heating. When the burner is regulated to produce a hot, blue flame it can be nearly invisible against some backgrounds. Increasing the amount of fuel gas flow through the tube by opening the needle valve will of course increase the size of the flame. However, unless the airflow is adjusted as well, the flame temperature will decrease because an increased amount of gas is now mixed with the same amount of air, starving the flame of oxygen. The blue flame in a Bunsen burner is hotter than the red flame. Many lab accidents are related to burn injuries or exposed flames, and as a result new students are trained carefully in the use of a Bunsen burner. In general, the user should make sure that hair and clothing are secure, and unlikely to fall into the flame. In addition, flammable chemicals should be kept away from the Bunsen burner, and someone should remain by the burner at all times to supervise it. The flexible rubber hose connecting the Bunsen burner to the gas nozzle on the lab bench should also be secure, with no evidnce of leaking, and people should be cautious about touching things which have been exposed to the often considerable heat of a Bunsen burner, especially glass objects.
