Questions tagged [combustion]
160 questions
128
votes
7 answers
Why does the humidifier make a stove's flame orange?
Just like this guy's, the color of my stove's flames were affected by the humidifier as well.
Why does this happen?
Is it a good thing or a bad thing ?
Ilya Gazman
- 2,177
49
votes
3 answers
How does water help extinguish fire?
How does water extinguish fire? Heat energy from the fire is transferred to the water, isn't that how it works? How does water deprive oxygen and stop combustion? How is the specific heat of water connected to this? If we use hot water instead cold…
user42836
- 658
46
votes
2 answers
Why doesn't increasing the temperature of something like wood or paper set them on fire?
Imagine we have paper book. If we put this into a pan and increase its temperature, this book would not catch on fire. If on the other hand the book interacts with this heat source directly, it does catch fire. What is the difference between these…
M. Çağlar TUFAN
- 709
42
votes
7 answers
Bush fires and heat waves, the real mechanics?
Like many others, I have been following the sad development of the bush/forest fires in Australia recently. A claim that gets repeated is that one of the contributors to this blaze is the ongoing >45°C heatwave.
Now I am not really putting this in…
Elmore
- 616
34
votes
3 answers
Why do two flames kept side by side merge into a single flame?
I have read about why a candle flame is in the shape of a tear drop in the presence of gravity. The top portion which is sharp is directly above the wick, where the soot particles from the wick rise up due to buoyancy and burn.
However, when I keep…
scienceauror
- 565
32
votes
3 answers
Why do particles in the molten wax near a burning candle wick get pushed away?
Have a look at this clip I made of my candle burning:
I can accept that the molten wax gets sucked into the wick (though not quite sure why: capilary action?).
But why does it also seem to get thrown outwards when it reaches the wick? I would…
turnip
- 3,768
31
votes
8 answers
If air is a bad conductor, how does fire heat up a room?
If air is a bad heat conductor, how does fire heat up a room?
Could someone help me, as I really don't get this?
Kaira Chunawala
- 451
30
votes
4 answers
How big is a 1kW fire?
What is the size/scale of a wood fire that is producing 1kW?
I'd like to improve my ability to conceptualize various power scales.
Dave
- 4,203
20
votes
3 answers
Why doesn't a cigarette lighter generate thrust?
The way thrust is created by a rocket is discussed here: How does fire create thrust in rocket?
If you look at a typical rocket, say V2, it has two primary tanks — one which stores the fuel and the other which stores oxygen. Is it that the lighter…
Shashank Sawant
- 671
19
votes
5 answers
Does fire emit black-body radiation?
Question: Can the radiation emitted by fire be approximated by black body spectrum?
It has been discussed in this community that black-body spectrum mostly serves as an approximation to actual spectra of thermal light sources:
firstly because…
Roger V.
- 68,984
17
votes
1 answer
Why can there be fire in space while there is no oxygen?
The sun is made of fire but fire needs oxygen right? So..
Why can there be flames in space, while there's no oxygen?
Same idea as with the rocket engines of the spaceship, which also produce fire while there's no oxygen?
Wouter Dorgelo
- 353
17
votes
3 answers
Why is the bottom part of a candle flame blue?
What’s the explanation behind the bottom part of a candle flame being blue? I googled hard in vain. I read this. I don’t understand how it’s explained by the emission of excited molecular radicals in the flame. I read that a radical is a molecule or…
Michael Dy
- 187
13
votes
3 answers
Can we call rusting of iron a combustion reaction?
In case of rusting of iron the chemical reaction is not fast enough. The oxygen used is not molecular oxygen from the atmosphere but it is the oxygen from water molecule. The reaction is not rapid and appreciable amount of heat is also not produced.…
Shinnaaan
- 1,455
13
votes
6 answers
What happens to the mass of a burned object?
If I were to burn a pile of wood weighing a hundred kilograms and I would have a big sack hanging over the burning pile. In this sack I would catch all the smoke that came from the burning pile, if all the wood turned to ashes and I'd put this in…
Daan Rijks
- 179
13
votes
1 answer
How do candles and wicks work?
The wick of my tea candle was buried in wax. So I lit a piece of paper and stuck it in the wax. Now the wax is burning off the paper, as if that were the wick.
The wax itself wouldn't light on fire without a wick, yet clearly what's burning is the…
isomorphismes
- 597