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Wood is a hygroscopic material. That is, it tends to absorb moisture from the air. Normally, it contains about eight per cent of water. However, it varies slightly depending on the atmospheric conditions of tumidity, etc. to which it is exposed over a period of time. Such a wood constitutes "dry wood".
But when wood is directly exposed to rain, etc, considerably, the water content becomes high. Such a wood constitutes "wet wood". However, the water does not alter the chemical composition of the wood. Water boils at 100 degrees C at sea level. If the water is heated further, it becomes steam at the same temperature. Obviously, heat is required for the conversion. This heat is known as the latent heat of vaporization (evaporation) of steam (water). It is 540 calories per gram - a highly significant value.
Wood is basically made of carbon, hydrogen and oxygen. However, they are in the form of polymeric materials, like cellulose. Of these, carbon and hydrogen are the fuels. The oxygen, along with the oxygen in the atmosphere, causes the fuels to burn. Broadly, there are four stages (sequences) of fire: incipient, smouldering, flame and heat. Initially, the wood is to be ignited (lit) by an external heat source, say, a match. When the wood reaches a temperature of about 150 degrees C, the cellulosic material starts decomposing (thermal decomposition and degradation).
There is no visible smoke, flame or significant development of heat. However, a large number of combustible particles are produced. This constitutes the incipient stage. As this stage continues, the combustible particles increase until they become visible -- a condition called "smoke". Smoke is made up of compounds of carbon, hydrogen and oxygen. But, no flame or significant heat develops at this stage also.
This is the smouldering" stage. As the fire condition develops further, ignition occurs and flame starts at about 500 degrees C. The level of visible smoke decreases and the heat level increase. This is the 'flame" stage. finally, large amounts of heat, flame, smoke and toxic gases are produced. This constitutes the "heat" stage.
During the incipient and smouldering stages, the water also starts getting heated up. In fact, it starts boiling at 100 degrees C, itself. Further on, it gets evaporated into steam. In the case of wet wood, a very high proportion of heat is taken away as the latent heat of evaporation. Therefore, there will be a hindrance for reaching even the third stage, let alone the fourth one.
However, the second (smouldering) stage continues without any hindrance. Accordingly. more smoke is produced when wet wood burns.
The specific heat of water is very high (one cal/g degrees C) as compared to that of wood (say, 0.55 cal/g degrees C). In absolute terms, this causes a significant heat dilution in the system. However, when the issue is "wet wood" vis-a-vis "dry wood", the effect can be ignored.
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What happens to wood as it burns?
It turns into ash and smoke.
Where does wood go when it burns?
I believe that it turns into ashes and smoke.
What type of energy are produced when the wood burns?
Chemical energy
Wood in a fireplace or the ashes in the fireplace after the wood burns has more potential energy?
Wood in a fireplace. When woods burns it gives of heat, a form of energy. Thus the wood has more potential energy.
Does the type of wood afeect how it burns?
Yes, the type of wood does affect of how it burns. Some types of wood have a thick bark which lets thick smoke out. On the other side if it does not have thick bark it won't burn as well as thick bark.
When wet wood burns what happens?
All the Bad smoke goes out in the worldand it is harder for animals and people to breath. Hello peepz
Is it a chemical reaction when a piece of wood burns?
It is oxidation as the wood combines with air.
Is the smoke emitted from gas heating worse then smoke from wood heating?
Gas heating does not produce any "smoke" at all. Wood burning, however, produces smoke which is much more toxic than tobacco secondhand smoke. It is best to completely avoid wood heating.
Do higher Smoke Developed Index values indicate more smoke or less smoke?
Higher Smoke Developed Index (SDI) equals a higher smoke development rate. The SDI is simply a measure of the concentration of smoke a material emits as it burns. Like Flame Spread Index, it is based on an arbitrary scale in which asbestos-cement board has a value of 0, and red oak wood has 100.
Is tobacco smoke worse than wood smoke?
Wood smoke is much worse than tobacco second hand smoke. Wood smoke contains more than twelve times as many carcinogenic compounds, and is chemically active up to forty times longer in the lungs than tobacco.
Why do we use wood in match sticks?
Matchsticks are made of wood or paper because it burns after the initial flame is created by the chemicals. The rate is slow enough to give you a few seconds to light you smoke or a candle.
When a match stick is burned what will happen?
Among other things:* You'll no longer have a match stick.* The wood of the match stick will convert to smoke; among other things, CO2 will be produced.* In the process, some oxygen will be used up.
