Questions about "methanol vapor burning in a plastic jug"?

Question

("Methanol vapor burning in a plastic jug" = "alcohol rocket car" = "whoosh bottle alcohol explosion")

I'm a sophomore, in high school, and this is my chosen end-of-the-semester demonstration. Problem is, I have a lot of problems answering some obvious questions as I was doing it.

1. Why is there a blue (then magenta/red/pink and orange) flame? What causes this; is it the oxygen exposure?

2. What causes the loud "whoosh" sound?

3. Why is the jug hot?

4. Why do we wait for the methanol to vaporize?

5. What does oxygen contribute to this reaction?

6. How is water and carbon dioxide the products of methanol?

7. Where in the world is the water (one of the product) derived from?

Keep in mind that I was using methanol, not ethanol or any other kind of alcohol, in this demo.

Also, I would really love to have these answers as soon as possible.

Thank-you so much!

Answer 1

1. No it's the methanol is a highly explosif gas. It absorbs heat very quickly which is what makes the flame change color

2. the whoosh sound is created by the oxygen trying to get in and the methanol trying to get out very quickly from a very small hole

3.The jug is extremly hot because the methanol would explode if it was in contact with oxygene. Since inside the jug, there is practicly no oxygene, it holds heat. This is why the jug gets hot because inside it is holding heat in.

4. If we didnt wait for the methanol to vaporise, it would create an explosion and you would prolly die.

5. For a fire (explosion) to happen, you need 3 elements, heat, a burner and a burning (soryy i dunno if those are the rigth terms, i learned them in french) The thing getting burned is always the oxygen (alone or with an organic material such as wood or paper) Without oxygene the metanol wouldnt explode

6. I'm not too sure about this one, but it's probably with the moleculs. Water is H2O and carbone dioxide is CO2. Methanol must be a mix of those two moleculs. Did the teahcer give you the molecular equation?

7. The water comes from the reaction. You have to look at you molecular equation ( each prodoct at the beiginning and at the end) Water is H2O so it means that the reaction seperated moleculs from the methanol and those moleculs got paired up with some others that creat H2O. Basiclly a reaction is just moleculs getting broken and reformed with other moleculs. Im not sure but i would guess in the methanol's moleculs, there is hydrogen (highly explosif, what creates the burning) and that hydrogen moleculs would form water with the oxygen that is burnign

Answer 2

hopefully this is sufficient:

1: the different colors are byproducts of the heat being released. this is something which can be witnessed in any flame: the center of the flame (the hottest part) is white, then blue and fades out to a lower heated yellow. it is not really related to O2 only that it is needed to sustain the reaction.

2: the loud whoosh sound is the escaping gasses through the nozzle

3: heat is a by product of combustion, well technically not a by product it is a result of it.

4:you need to wait for it to vaporize because methanol is not combusable as a liguid; you can extinguish a lit match with liquid alcahol but should any vapors reach it it will catch.

5: due to the inability to adequately diagram a chem reaction here beyond 2 CH3OH + 3 O2 → 2 CO2 + 4 H2O suffice it to say that it would not be possible to "burn" without it.

6: see aforementioned reaction

7: again see aforementioned reaction.

just as a post script, methanol is methyl alcohol better known as wood alchohol; never drink the stuff it will make you blind!

Answer 3

1. As the oxygn in the bottle is used up in the combustion of the methanol, incomplete combustion begins to take place yielding a cooler (redder) flame.



2. Hot gases like CO CO2 and water vapor escaping.



3. Combustion produces heat.



4. Liquid methanol burns slowly.



5. Oxidizes the carbon in the methanol (CH3OH) to CO2



6. Products of combustion.



7. Also a product of combustion.





Next time use isopropyl alcohol. It is less toxic, less flammable, and doesn't cause blindness if accidentally swallowed.

Answer 4

i'm reposting your considerate question right here in my answer. The poet-fact seeker reported this : "some purely holiday on Paths - mutually as others holiday for the era of trackless deserts - people who holiday on Paths - Can see their thank you to GOD. people who holiday on trackless deserts are like people who've lost their thank you to God. GOD, nicely-knownshows in the Souls of the two! For He, is the indoors fact, the sunshine interior of all and sundry. that's what, Ibn Arabi wrote, which isn't purely amazing, yet definitely inspired by Divinity. I wish I had examine his entire paintings. I do understand approximately trackless deserts as men dropping there way and not looking the course. as quickly as a guy has got here upon the course then it is the way a guy will seek for God. i assume then that once a guy is on the course he can flow in any course to discover the signs and indicators which will lead him to the place God is. while they have got here upon God, God can mild the hearth interior of him so as that he too turns right into a bearer of the fact and stay that existence in the pathway of fact. Which brings me to a different theory. The signs and indicators someone's sees is the two an adventure or a individual that could reason a guy to alter his course in existence. And to choose to seek for God had his mild of their darkish worldwide it is calling for for God's fact and lightweight yet don't are conscious of it.