Assuming the contents are what is written on the outside, compressed air is a mixture of about $78~\%$ nitrogen, $21~\%$ oxygen, $1~\%$ argon and about $0.04~\%$ carbon dioxide. None of these compounds are flammable. Oxygen, however, is able to support combustion. So increasing the amount of oxygen a flame gets will increase combustion.
The principle difference between blowing canned compressed air onto a candle flame and simply blowing into said candle flame is the focus of the air flow. These cans are designed to blow air in a rather defined way to a defined target so you can assume the air flow to be very focused. Blowing using your mouth would create a very unfocused air flow because there is only one constraint (your lips) and air can pass through at a variety of angles.
When reaching the candle flame, the focused air flow causes the mixing of gaseous wax (required for combustion) and oxygen from the air (both the canned and the uncanned) to improve, hence increasing the rate and heat of combustion. The small focused flow will create small whirls that help mixing. The mouth-blown air, however, will come as a strong wave, practically pushing the entire candle flame away. Therefore, the flame will go out. (That and only that is the mechanism of blowing out candles: blowing the flame away.)
Assuming the contents are what is written on the outside, compressed air is a mixture of about $78~\%$ nitrogen, $21~\%$ oxygen, $1~\%$ argon and about $0.04~\%$ carbon dioxide. None of these compounds are flammable. Oxygen, however, is able to support combustion. So increasing the amount of oxygen a flame gets will increase combustion.
The principle difference between blowing canned compressed air onto a candle flame and simply blowing into said candle flame is the focus of the air flow. These cans are designed to blow air in a rather defined way to a defined target so you can assume the air flow to be very focused. Blowing using your mouth would create a very unfocused air flow because there is only one constraint (your lips) and air can pass through at a variety of angles.
When reaching the candle flame, the focused air flow causes the mixing of gaseous wax (required for combustion) and oxygen from the air (both the canned and the uncanned) to improve, hence increasing the rate and heat of combustion. The small focused flow will create small whirls that help mixing. The mouth-blown air, however, will come as a strong wave, practically pushing the entire candle flame away. Therefore, the flame will go out. (That and only that is the mechanism of blowing out candles: blowing the flame away.)
In former centuries the word "air" was used to descrive gases generally, not what chemists call "air" today. Hydrogen used to be "fire air". Sometimes this usage still creeps in, I've heard people use "air knives" for devices that wipe excess coating off a hot dip galvanized strip with nitrogen gas.
Don't rely on just the product name used to sell the product. Check all the labelling. If there is something (in)flammable, the manufacturer is required to report that information.
In former centuries the word "air" was used to descrive gases generally, not what chemists call "air" today. Hydrogen used to be "fire air". Sometimes this usage still creeps in, I've heard people use "air knives" for devices that wipe excess coating off a hot dip galvanized strip with nitrogen gas.
Don't rely on just the product name used to sell the product. Check all the labelling. If there is something (in)flammable, the manufacturer is required to report that information.
Most probably some hydrocarbon like butane = big flame. A quick way to check is if the can makes a sound when you shake it. If it does then it's most likely hydrocarbon. It would have been less confusing if it said "compressed gas".
Most probably some hydrocarbon like butane = big flame. A quick way to check is if the can makes a sound when you shake it. If it does then it's most likely hydrocarbon. It would have been less confusing if it said "compressed gas".
Assuming the contents are what is written on the outside, compressed air is a mixture of about $78~\%$ nitrogen, $21~\%$ oxygen, $1~\%$ argon and about $0.04~\%$ carbon dioxide. None of these compounds are flammable. Oxygen, however, is able to support combustion. So increasing the amount of oxygen a flame gets will increase combustion.
The principle difference between blowing canned compressed air onto a candle flame and simply blowing into said candle flame is the focus of the air flow. These cans are designed to blow air in a rather defined way to a defined target so you can assume the air flow to be very focused. Blowing using your mouth would create a very unfocused air flow because there is only one constraint (your lips) and air can pass through at a variety of angles.
When reaching the candle flame, the focused air flow causes the mixing of gaseous wax (required for combustion) and oxygen from the air (both the canned and the uncanned) to improve, hence increasing the rate and heat of combustion. The small focused flow will create small whirls that help mixing. The mouth-blown air, however, will come as a strong wave, practically pushing the entire candle flame away. Therefore, the flame will go out. (That and only that is the mechanism of blowing out candles: blowing the flame away.)
Assuming the contents are what is written on the outside, compressed air is a mixture of about $78~\%$ nitrogen, $21~\%$ oxygen, $1~\%$ argon and about $0.04~\%$ carbon dioxide. None of these compounds are flammable. Oxygen, however, is able to support combustion. So increasing the amount of oxygen a flame gets will increase combustion.
The principle difference between blowing canned compressed air onto a candle flame and simply blowing into said candle flame is the focus of the air flow. These cans are designed to blow air in a rather defined way to a defined target so you can assume the air flow to be very focused. Blowing using your mouth would create a very unfocused air flow because there is only one constraint (your lips) and air can pass through at a variety of angles.
When reaching the candle flame, the focused air flow causes the mixing of gaseous wax (required for combustion) and oxygen from the air (both the canned and the uncanned) to improve, hence increasing the rate and heat of combustion. The small focused flow will create small whirls that help mixing. The mouth-blown air, however, will come as a strong wave, practically pushing the entire candle flame away. Therefore, the flame will go out. (That and only that is the mechanism of blowing out candles: blowing the flame away.)
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In former centuries the word "air" was used to descrive gases generally, not what chemists call "air" today. Hydrogen used to be "fire air". Sometimes this usage still creeps in, I've heard people use "air knives" for devices that wipe excess coating off a hot dip galvanized strip with nitrogen gas.
Don't rely on just the product name used to sell the product. Check all the labelling. If there is something (in)flammable, the manufacturer is required to report that information.
In former centuries the word "air" was used to descrive gases generally, not what chemists call "air" today. Hydrogen used to be "fire air". Sometimes this usage still creeps in, I've heard people use "air knives" for devices that wipe excess coating off a hot dip galvanized strip with nitrogen gas.
Don't rely on just the product name used to sell the product. Check all the labelling. If there is something (in)flammable, the manufacturer is required to report that information.
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VOTE
Most probably some hydrocarbon like butane = big flame. A quick way to check is if the can makes a sound when you shake it. If it does then it's most likely hydrocarbon. It would have been less confusing if it said "compressed gas".
Most probably some hydrocarbon like butane = big flame. A quick way to check is if the can makes a sound when you shake it. If it does then it's most likely hydrocarbon. It would have been less confusing if it said "compressed gas".
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VOTE