Oxygen fuels fires, but a gust of wind will blow out a candle - why is this so?

Answer 1

In a fire, Oxygen is not the fuel, it is the oxidizer. Depending upon what is burning, the fuel could be any number of things.
Oxygen does not burn, but is required for combustion.

In order for something to burn, 3 things are necessary,
-Fuel
-An oxidizer (Oxygen)
-[activation] Energy

Unless these 3 things are present, the object in question will not burn.
If we assume fuel and Oxidizer are plentiful, then the only thing left which will keep something from burning is that extra bit of energy needed to set off the reaction. After one gets a fire going, usually, this energy is provided by the excess heat the fire generates, but it needs to be supplied initially by some form (for example, lighting a match to start light a candle).
If one were to take away the fire's ability to provide its own activation energy, it would go out unless supplemented by some outside source.

When a gust of wind blow out a fire, it is blowing away the energy the fire needs to burn, it is cooling it off too much for it to continue burning.

Answer 2

Oxygen is a vital component in combustion reactions which is why it produces fire. However, a combustion reaction requires an initial input of energy, like the match that lights the candle. Normally, combustion reactions can produce enough energy to keep the process going. The gust of wind that blows out the candle carries away enough energy as to prevent the reaction from starting again, thus putting the candle out.

Answer 3

When you "blow" on a candle, you are cooling the fire and it goes out. There isn't enough fuel present to offset the amount of cooling effect the movement of the air is having. That's why if you "blow" on a larger fire, with more fuel load, it briefly intensifies (because you are providing more oxygen). That's the whole idea behind a bellows.

Wanna know something else interesting? If you take that same candle after you blow it out and place it in an oxygen rich environment, it will reignite! Cool, huh?

Answer 4

I don't have a scientific answer, but I think it's because the air we breathe isn't flammable. It is a requirement for fire, but wind won't hit a flame and ignite...and because of the nature of fire, the flame goes out.

Answer 5

It actually cuts off the air flow to the fire because it is blowing too hard. It smothers the fire with fast moving air which it cannot combust.

Answer 6

my guess is that the force of the wind knocks the flame out. Still oxygen enables the flame, but when it gets gusty... it is stronger than the flame and puts it out...

Answer 7

because the wind is coming at a force and wind isn't pure oxygen

Answer 8

Because of the "motion" of the air.

Answer 9

There's too much pressure for the flame......food is good for our bodies but too much food is not. "It is but is isn't"

Answer 10

Quantity is the answer.