Why when burning, the fire always rises?

Although used regularly for a long time, but the fire always upward not everyone can explain.

First we need to understand the nature of the fire, an important invention that helps people become different from other species. It is hard to imagine what kind of society would be like without fire.

Picture 1 of Why when burning, the fire always rises?
Man uses fire skillfully.

What is the fire, why is there fire?

Matter is composed of billions of atoms, and always remains the same. Fire is not: fire can transform into other forms - it is part of chemical reactions .

Flame exists due to chemical reactions between oxygen in the air and fuel or combustible materials.

However, the condition of the reaction is to have the action to make the burning object reach the point of fire. This effect may be rubbing or thermal. Then the fire reaction takes place and we have a fire.

Picture 2 of Why when burning, the fire always rises?
Three elements make up the fire.

The reaction of fire burns a lot of heat. It is this that maintains the fire, and makes the fire spread.

The heat generated by that fire maintains the material at the ignition temperature, so the fire continues until there is nothing left to burn or until a new human intervention.

Besides heat, the reaction of fire accompanied by shine. What color the flame depends on the material burning, and the heat of the flame. Uneven colors in the fire are caused by temperature heterogeneity.

Watch a video explaining why the fire is facing up:

Why fire burn upwards?

One characteristic of burning is that the flame is always directed upwards. Why is that?

Rationale: The fact that the flame is always pointing upward is the result of the movement generated by air during combustion (convection).

Picture 3 of Why when burning, the fire always rises?
Convection phenomenon makes the flame always upwards.

The air around the flame is heated because the density of hot air is smaller than that of cold air, the hot air rises upward, and the cold air component will overflow with additional replacements.

When hot air flows upwards, the flames will be drawn upwards. When burning a large bonfire, the amount of hot air rises very large, and cold air rushes in so making flames rise stronger.

Picture 4 of Why when burning, the fire always rises?
Come on up!

In addition, because the combustion is a chemical reaction involving oxygen, gases will be generated after the reaction such as CO 2 , NO 2 . (smoke).

They have a lighter density than air (including many gases such as oxygen, nitrogen .), so they will stay on those gases, moreover in areas with high temperatures, the pressure is higher than elsewhere.

In fact, the airflow is influenced by many factors, so the flow of air is always disturbed. It has affected the movement of the hot air stream causing the flame to become unstable.

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