Strike back occurs when there is too much oxygen and create a green flame at the jet of the Bunsen Burner and creates a loud noise. This only occur when the air hole is fully open.
What part of the Bunsen burner does the fuel burn when it strikes back?
The gas “blows back”, “strikes back”. The gas is burning inside the barrel . Turn the gas fully on and strike the gas supply rubber tube with a sharp blow from the side of your hand. If the flame does not reappear, immediately turn the gas off and leave to cool because the barrel may be hot.
What is needed for burning to occur in Bunsen burner?
Sufficient oxygen is needed for complete combustion. Complete combustion of methane pro- duces a blue, non-luminous flame yielding carbon dioxide and water. ... Bunsen burners (named after Robert Bunsen, 1811–1899) were designed to generate a combustible gas–air mixture that pro- duces an efficient, hot flame.
What should you do if the force of the gas extinguishes the match flame?
If the force of the gas blows out the match, repeat the operation with the match held further from the center of the gas stream and turn the gas on slower this time. Consult your instructor if you have any further difficulty. To extinguish the flame, close the gas outlet on the benchtop by turning the valve quickly .
What causes burners to strike back?
With too little air , the gas mixture will not burn completely and will form tiny carbon particles that are heated to glowing, making the flame luminous. With too much air, the flame may burn inside the burner tube; that is, it may strike back.
What should we do when a strike back occurs?
This condition, known as strike back, heats the barrel to dangerously high temperatures. Should strike back occur, extinguish the flame immediately by closing the bench valve . Once your flame has been properly adjusted, extinguish the flame by rapidly turning the bench valve to the closed position.
How will you prevent a burner from striking back?
Tie back your hair and take off scarves in order to prevent them from catching fire by mistake. Close the gas supply immediately when the flame strikes back because of excess air supply. If the gas burner is not used for some time, set it to luminous flame and reduce the gas flow.
What should you do if your Bunsen burner does not light after a few tries?
If the burner doesn’t light after several strikes, turn the gas off at the source . Verify that you are generating sparks when striking the striker, and check that the barrel is all the way down and the needle valve is open by the specified amount. If these check out, the problem may be insufficient gas flow.
What happens to the flame when you increase the gas flow?
Increasing the air flow to the burner produces more complete combustion and a hotter flame. The air is increased by opening up the air vent (turning the metal collar) . ... Sometimes when the air flow is being adjusted, the flame may “blow out.” If this happens, simply turn off the gas and close the air vent.
What is the flame that you should always light the Bunsen burner on?
Adjust flame by turning the collar to regulate air flow and produce an appropriate flame for the experiment ( typically a medium blue flame ). During Use: Never leave a lighted burner unattended.
What is the difference between luminous and Nonluminous flame?
While a luminous flame burns yellow, a non-luminous flame burns blue ; this is because of the difference in available levels of oxygen. Luminous flames have limited access to oxygen, while non-luminous flames have unlimited access to oxygen.
What is needed for burning to occur?
The Fire Triangle. Three things are required in proper combination before ignition and combustion can take place —Heat, Oxygen and Fuel . ... There must be Air to supply oxygen. There must be Heat (ignition temperature) to start and continue the combustion process.
What should be done with the wastes in the flame test experiment?
What should be done with the wastes in the Flame Test experiment? They should be disposed of in the labeled container. They should be thrown in the trash can beneath the sink. They should be flushed down the sink with plenty of water .
Which part of a flame is hotter?
Actually, the hottest part of the candle flame is the blue part , at 2552 degrees F (1400 C.) That is where the flame has the most oxygen and you are getting complete combustion. The reddish part is the coolest part, about 1472 F (800C).
How do you control the height of the flame?
Adjusting the Flame. Use the needle valve to control the flame’s size. The needle valve on the bottom of the Bunsen burner adjusts the gas flow rate, which determines the height of the flame. More gas will create a larger flame, and less gas gives you a smaller flame.
What color flame is the hottest?
While blue represents cooler colors to most, it is the opposite in fires, meaning they are the hottest flames. When all flame colors combine, the color is white-blue which is the hottest. Most fires are the result of a chemical reaction between a fuel and oxygen called combustion.
