Chemistry Laboratory 101 Sec F Activity Number 1 Title: The Bunsen burner Group 1 Aceberos, Jamila Alfeiya S. Torres, Dayanara F. Tortola, Krizel T. 1. Objectives: To be able to … a) … Acquire knowledge about abou t the different parts of the Bunsen burner. b) … Investigate the parts of the flame. What it produces and the effects it may undergo in certain conditions. 2. Materials/ Chemicals Ø Bunsen burner Ø Glass tubing Ø 4” x 4” cardboard Ø Charcoal 3. Data, Result and Discussion. I. CLEANING AND EXAMINATION After unscrewing, examining, cleaning and reassembling the Bunsen burner, we were able to distinguish different parts of the burner. Those were the base, gas regulator, gas inlet, air hole, barrel, the collar and the gas spud. We’ve discussed some of its function by our own understanding of how it works. Since didn’t test it. We come up remembering our past lessons on chemistry. A) Base - It is the main frame that holds the hole body of the Bunsen Bun sen burner B) Gas regulator – it adjusts the flame. C) Gas inlet – where the gas ga s enter from the gas pipe connected by rubber tubing to the burner. D) Air hole – where the air is regulated to produced luminous flame. E) Barrel – is the body of the burner where the flame comes out. F) Collar – regulates the air hole tightly or loosely. G) Gas spud – where the gas passes from the gas inlet to the barrel. II. OPERATION Operations follow, lighting the Bunsen burner, adjusting the air holes (which produces nonluminous flame) and jotting the difference on the deposit when a porcelain dish is put p ut above the flame. The table below shows the difference between the two flames produced. Difference on the Deposit of the two Flames Produced by the Bunsen Burner Type of flame Deposit it Produced luminous flame ( orange to yellow color ) The deposit on the flame is black, charcoal-like material
Non-Luminous flame ( blue color ) There is NO DEPOSIT produced in this type of flame. In the data we have gathered, we agreed that the luminous flames contain a carbon which is why it has produced a black deposit. The charcoal-like effect was the same as the effect produced by any other ordinary flame produced in household chores. The air that enters the burner helps the luminous flame oxidize and the result is that a non-luminous flame. What question us is why that then non- luminous flame is efficient and making it perfect in heating materials. Another question is that why when we are lighting papers for burning charcoals is and always produces an orange to yellow flame even though air is already present in the atmosphere. III. Investigating the Flame Investigating the flame by showing changes undergoes during certain conditions. The result shows below. Spraying powdered charcoal Ø The flame sparkles and from non-luminous to luminous flame. Until all the charcoals are gone the flame returns to its blue color. Lighting a match stick Glass tubing inserted in the burner Ø The match stick produces flame and there are signs of moisture in the process of lighting. The flame also changes from blue to orange-yellow flame. Ø When the glass tube is inserted in the inner core of the barrel, the gas passes thought the tube and when lighted, it also gave a non-luminous flame. Wet piece of cardboard Ø After 20-03 seconds of exposure to the flame the board dried up starting from the lowest part to its tip. Forming a Pyramid-like shape. By the above result shows all three of us wondered why the flame changes from blue to orangeyellow, we have predicted that every time the blue colored flame is interrupted by other chemicals like the chemicals that produced charcoal and the match stick. The pyramid like shape of the cardboard was we propose the shape of the flame by nature. The portion of the cardboard where most of the char was been observe was suppose to be the hottest part of the flame. 4. Questions and Answers. Review questions 1) What are the functions of the gas valve, the air holes and the barrel? Ø Gas valve – is the where the gas comes from. It is synonymous to the faucet of water. It is the outlet of the gas where the rubber tubing is attached. Ø Air holes – where the oxygen is regulated to produce non-luminous flame Ø Barrel - body of the burner where the body comes out. 2) Is “presentability” the only reason why the laboratory burner is cleaned? What other reason is
there? Ø No. it is cleaned for it may contain chemical which may contaminate the flame and blast off. Since we are dealing with flammable laboratory apparatus, it is VERY IMPORTANT to be very clean because there are chemicals which are flammable and can cause serious fires and can harm the entire surroundings. 3) The operation of the Bunsen burner is laid out in specifics. Why should the steps be followed strictly? Ø It should be followed strictly because things might badly hap pen when it is not properly followed. One of the accidents that may happen is when the gas regulator is open. Upon opening the gas valve the gas will be out in the barrel. Gas may leak producing not so good odor and when we will light it the flame will roar in a surprised producing some of the common accidents that happens in the laboratory. 4) Explain the ratio of the fuel to air (oxygen) to produce a non-luminous (blue) flame? Ø It contains a fully mixed oxygen flame. 5) The scorched regions of the cardboard indicate the varying intensities of the heat. What is the practical value for this knowledge? Ø Because the position of the cardboard is vertical it obviously displays the intensities of the heat. The bottom of the cardboard displays the hottest part of the flame where the char is first seen. While the top area of the cardboard took time to dry up and char because is cooler in this area that those at the bottom. 5. Conclusion The Bunsen burner is one of the most important laboratory equipment which every laboratory student must have expertise with. It is what helps us heat materials which is one of the procedure most frequently used in laboratory. Knowing the 7 main parts of the burner, the base, gas regulator, gas inlet, air hole, barrel, collar and the gas spud is important because the operation of the burner is strictly followed for safety purposes. There are two flames that can be produced in a gas burner. First is the luminous flame which varies from orange to yellow. This type of flame does not undergo complete combustion because the air it gets is less. The luminous flame is also called “dirty” flame because it leaves a layer of carbon whatever it heats, like the porcelain dish in the activity. The second is the non-luminous flame or the blue colored flame. Here, the air holes are open which let the air combined with the gas, undergoing complete combustion. It is the most efficient flame in heating in laboratory. The non-luminous flame changes to luminous u pon the interruption of other chemicals present like the presence of carbon.
