You are in a chemistry lab and you need to do a distillation. There is a possibility that you need to use a Bunsen burner to heat the liquid mixture until it boils. In fact, Bunsen burners are the most used heat source in elementary, organic or inorganic chemistry laboratories. Turning them on and adjusting them won't force you to run out of patience anyway, even if you're inexperienced.
Steps
Part 1 of 5: Ensure a safe environment
Step 1. Make sure you have a clean and tidy workspace
It is also a good idea to make sure you are working on a fire retardant bench, or at least a fire retardant carpet.
Step 2. Check that all equipment is clean and in order to work
Step 3. Make sure you know where the safety equipment is and how to use it
It would be best to have a look at all the premises before starting any experiments. In particular, make sure you can freely use the following things:
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A fireproof blanket.
Use it to wrap it up if you want to stop the fire. The blanket will suffocate the flame depriving it of the necessary oxygen.
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Fire extinguishers.
Know each one's location. It won't hurt to know even if the upgrade inspection has been done. At the same time, you can choose the available templates and organize an action plan in case of an emergency. There are several types of fire extinguisher and each is marked with a colored ring on top.
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Dry retardant powder can be used on all types of fires, except oil fires.
Powder fire extinguishers can be used on usual, liquid, gas and electrical equipment. Fire extinguishers that contain flame retardant powder are marked with a specific ring color. Find out about the color used in your country.
- Foam or CO2 they are for oil fires.
- The fire extinguishers in CO2 they can also be used on electrical equipment and flammable liquids.
- The foam can also be used on flammable liquids or solids (paper, wood, etc.).
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Learn how to use a fire extinguisher.
Pull the pin and, with the nozzle facing you, unlock the safety mechanism. Point down to the base of the fire. Pull the trigger on the fire extinguisher slowly and evenly. Spray the mixture by moving from side to side.
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A fire hose.
It is useful for large fires and should be used by people trained in the procedures. Spray at the base of the fire to cool the combustible material (the one that burns). Water can be used on solids such as wood, paper, clothing, furniture, etc., but not on flammable liquids such as gases, oils or even electrical equipment. Never use water on liquids less dense than water itself (1.0 g / cm3). Such liquids float to the surface and splashing water would only cause the fire to spread.
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A safety shower.
If your clothes catch fire and aren't impregnated with flammable liquid, it might be a good choice. The safety shower can first of all flush acids out of your body, but it can come in handy in the event of a fire.
Step 4. Dress to be safe
Wear safety glasses and use protective equipment when handling the Bunsen burner.
Make sure to keep your hair tied back if it's long and to secure loose clothing (or take it off). Also stop the tie and remove the jewelry. "Think ahead" and eliminate threats before they become real problems. There must be nothing that can catch fire
Step 5. Make sure there is no damage to the gas system, which usually consists of rubber hoses
Gently press the tubing to the full length and bend it in places while carefully checking for damage. If you find any, change the tube.
Step 6. Connect the pipes to the main gas system and to the Bunsen burner
Make sure the tube is well connected and secured at both ends. The gas must have no way out except from the beak.
Step 7. Get used to handling the beak from the bottom only
Hold the Bunsen burner only by the base or the collar at the bottom of the keg. Once the beak is lit, the stem will be very hot and you risk burning yourself if you take the beak from the top before it cools completely.
Part 2 of 5: Learn how the Bunsen burner works
Step 1. Learn the names of the parts of the Bunsen burner
- The bottom of the beak that rests on the table is called the base. The base provides stability and helps prevent the beak from tipping over.
- The vertical part of the beak is called the stem.
- At the bottom of the shell is an outer sheath (the collar) that can be rotated to expose the slots in the shell, called air ports. This will allow air to enter the drum where it will be mixed with the gas to produce a highly flammable gaseous compound.
- The gas enters the keg through a needle valve which can be adjusted to control the flow.
Step 2. Learn the composition of the flame
There is a real flame in the flame. The internal flame is the reduction flame, the external one is the oxidation flame. The hottest part of the flame is the tip of the inner flame.
Step 3. Learn the specific components of the gaseous compound and the combustion process
- Air and gas mix in the keg. If the collar is turned to close the air ports, no air will enter the keg. All the oxygen (necessary for combustion) is introduced from the top of the barrel, from the surrounding air. The flame will be yellow and will be the coldest. It is often called a safety flame. When the beak is not in use, the collar must be rotated in such a way as to close the air ports and produce the cold safety flame.
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The needle valve and the collar are used together to control the volume and the right percentage of gas to be introduced. The amount of gas introduced largely determines the amount of heat produced. An equal amount of gas and air produces the hottest flame. The total volume of the gaseous compound rising into the barrel determines the height of the flame.
You can open the needle valve and air ports slightly to achieve a warm, small flame, or you can let both streams in simultaneously to create a higher hot flame
Part 3 of 5: Turn on the Bunsen burner
Step 1. Make sure the collar near the bottom of the keg is positioned so that the air ports are nearly closed
Locate the openings in the base of the chimney and turn the outer metal crown (the collar) until the holes are closed. This will ensure that the flame is at its coldest point when the gas is introduced (safety flame).
Step 2. Make sure the local supply valve is closed and the laboratory gas system is turned on
The handle must cross the gas line, perpendicular to the outlet.
Step 3. Close the needle valve at the bottom of the spout
Make sure the burner is closed completely.
- You will need to light the match or have a gas lighter ready and then turn the handle (in line with the gas notch) and open the needle valve slightly. This will ensure you have a small flame initially.
- The best way to light a burner is by using a gas lighter. This tool uses a flint on metal to cause a spark.
- Try to cause lots of sparks, until you can generate a powerful spark with each hit. Push the stone towards the "knocker" as you lift it. This will allow you to emit a more powerful spark. Practice until you emit a powerful spark each time. You are now ready to light the burner.
Step 4. Open the local gas valve by turning the handle so it is parallel to the outlet
You shouldn't feel the gas flow at this point. If you feel it, immediately turn off the gas and the needle valve clockwise. Open the local gas valve again and make sure the gas lighter is within reach.
Step 5. Open the needle valve on the bottom of the burner until you hear the gas hiss coming out
Step 6. Hold the gas lighter 3-5cm just above the keg and press the gas lighter to create a spark
Once the burner is lit, put the gas lighter away.
If you don't have a gas lighter, you can use a match or a disposable lighter. Before opening the gas, light the match or lighter and hold it away from the burner, slightly to the side. Open the gas, then bring the ignition source to the side of the gas column. Once the flame is lit, put the match or lighter away. Let the match go out completely, then you can place it on the table, away from the experiment
Part 4 of 5: Adjust the Flame
Step 1. The needle valve at the bottom of the Bunsen burner regulates the gas flow and basically determines the height of the flame
Open or close the needle valve to give the right size to the flame based on the job to be done. Remember: the needle valve is the one that serves to increase or decrease the flame, not the closing valve.
To adjust the flame height, vary the gas flow by opening and closing the needle valve. More gas will give you a bigger flame; less gas, a smaller flame
Step 2. The collar controls the amount of air entering the keg (mixing chamber) and basically determines the temperature of the flame
Adjust the collar so that no air enters the keg for the colder flame, safety flame or pilot flame. When you are ready to heat something, open the air doors until the flame acquires the right color. A yellow flame is cold, a blue or nearly invisible flame is the hottest.
For a warmer flame, turn the collar on the bottom until the holes (the air ports) are fully open. Adjust it until you reach the desired heat
Step 3. Adjust the flame to reach the right working temperature for your experiment
- The hottest flame is sometimes called the "work flame". To create a blue flame, open the holes in the collar to allow more oxygen to enter the combustion chamber. The holes must be completely open or almost.
- A blue flame is very hot (around 1500 ° C) and is not easily visible. On some backgrounds, it can be almost invisible.
Step 4. Use different parts of the flame to further adjust the temperature
If you have to bend glass tubes, you will have to reach the hottest flame and, at the same time, at a medium height, then place the tubes on the reduction flame or immediately on its tip. If it is too hot, raise the pipes a little to the colder oxidation flame.
There are many adjustments to be learned through experiments and mistakes, but nothing is more important than safety. You will soon learn which colors the specific temperatures correspond to, at least in principle
Part 5 of 5: Check and Clean
Step 1. Do not leave a lit Bunsen burner unattended
Check it out every now and then. If you are working on something that does not involve the use of flame, turn it down to the coldest degree, over the yellow flame (the safety flame) by turning the collar until the holes are completely closed.
Step 2. Turn off the gas
Shut off the gas supply by placing the hand valve on the gas line.
Step 3. Wait for the burner to cool down
Five minutes will be enough, but still continue to handle the burner holding it only from the bottom. Get this habit.
Step 4. Close the needle valve by turning it clockwise
The valve will then be ready for the next use.
Step 5. Make sure the burner and piping are clean and in order to work before placing them in the drawer
When the burner is clean and the needle valve is closed, the risk of unexpected behavior is greatly reduced. Remember this important step.
Warnings
- Be sure to turn off the gas once you have finished the experiment with the burner.
- Watch out for anything that can tip the burner over or come into contact with the flame.
- Use the safety flame or turn off the burner completely when not in use.
- Do not touch never the flame or the top of the keg. You could get severe burns.
