How does blowing out fire work?
Table of Contents
- 1 How does blowing out fire work?
- 2 Is burning a candle a chemical or physical change?
- 3 Can blowing out a candle cause a fire?
- 4 Why does blowing on a smoldering fire make it burn better?
- 5 Do candles dry out the air?
- 6 Why do we extinguish the flame when we blow out a candle?
- 7 What happens when you take the heat away from a candle?
How does blowing out fire work?
When you blow, you cool down the gases and the surface of the candle and spread out the wax vapor. So when you blow on it, there’s no longer a region which has enough wax molecules in it and also is hot enough to get the reaction to occur.
When a candle burns What reaction does it produce?
When a candle burns, the reactants are fuel (the candlewick and wax) and oxygen (in the air). The products are carbon dioxide gas and water vapor.
Is burning a candle a chemical or physical change?
If the wax was simply undergoing physical change, would you expect the candle to produce heat and light as it does when a candle burns? The process of burning (as opposed to evaporating) is a chemical reaction, a chemical change.
Why does blowing on a candle extinguish it?
Carbon dioxide molecules are heavier than air. Because of this, they push the oxygen and other molecules in the air out of the way as they sink down over the flame and candle. When oxygen is pushed away from the wick, it can’t react with the wax anymore. This makes the flame go out.
Can blowing out a candle cause a fire?
Candles left unattended or too close to flammable items can trigger a fire that spread room to room and have the ability to destroy a whole house. Since candles are such a common piece of décor in homes, it’s important to know how to prevent these fires so you can keep using candles but do so safely.
Why does blowing on a candle make it go out?
Why does blowing on a smoldering fire make it burn better?
When you have a fire that is already smoldering, blowing on it will make it burn hotter and faster. When you can add more oxygen, you are going to increase the temperature and push it toward the fuel that has yet to catch. And the lower pressure you create with your breath helps even more because it’s more oxygen-rich.
What happens to a candle?
When you light the wick, the flame causes some of the wax to melt, flow up the wick and evaporate, and then the wax vapor burns. When a candle burns, the hydrogen and carbon from the wax combine with the oxygen in the air to become carbon dioxide and water vapor.
Do candles dry out the air?
Candles can’t dehumidify a room because they have hydrocarbons that produce carbon dioxide and water vapor when burnt. The water vapor causes an increase in humidity levels. Lighting many candles in a room translates to a higher humidity percentage. The smaller the room, the fewer candles you should light.
How does a candle work?
How Candles Burn. When you light a candle, the heat of the flame melts the wax near the wick. This liquid wax is then drawn up the wick by capillary action. The heat of the flame vaporizes the liquid wax (turns it into a hot gas), and starts to break down the hydrocarbons into molecules of hydrogen and carbon.
Why do we extinguish the flame when we blow out a candle?
When you blow out a candle, your breath contains more carbon dioxide than it did when you inhaled the air, but there’s still oxygen that can support wax combustion. So, you may be wondering why the flame is extinguished. It’s because a candle needs three things to sustain a flame: fuel, oxygen, and heat.
Why does a candle need oxygen to burn?
The candle already has a lot of oxygen available. What’s limiting it is the flow of evaporated wax up into the flame. That flow is driven by the heat given off by the flame itself. When you blow, you cool down the gases and the surface of the candle and spread out the wax vapor.
What happens when you take the heat away from a candle?
The heat overcomes the energy needed for the combustion reaction reaction. If you take it away, the flame can’t sustain itself. When you blow on a candle, you force the heat away from the wick. The wax drops below the temperature needed to support combustion and the flame goes out.
How do you extinguish a candle with an invisible gas?
The flame will be extinguished by the invisible gas. Another way to perform this trick is to pour the gas that you just made into an empty glass and then pour the apparently empty glass over the candle flame.