“No, we can’t melt wood. Even in a vacuum, wood cannot melt.”
We know that most of the solid substances have certain melting point but have you ever seen wood melting?
No right! Let’s first understand what is melting of a substance.
The process of changing a state that is changing from a solid state to a liquid state without altering its chemical makeup is known as melting. For example, solid ice changes its state from solid to liquid state i.e. water on heating.
Therefore when we starting heating wood, it should melt at a certain temperature and convert its state from solid to liquid. But we have seen that on heating wood starts burning and gets converted to charcoal and ash. So why wood gets combusted instead of melting.
Now let’s find out what happens when a wooden piece is heated. Here we have two situations: first heating wood under the presence of oxygen and second heating under vacuum conditions.
Heating wood under normal conditions (presence of oxygen)
In normal conditions, heating of wood will first remove the water present in it. Then it will get oxidized. Wood is a solid composed of cellulose, lignin, and other long-chain molecules. On heating, these molecules will react with oxygen and form ash along with carbon dioxide. This is an irreversible process in which the physical structure of the wood gets destroyed. But we know that the melting of a substance is a reversible process in which the chemical makeup remains the same. Therefore wood cannot melt.
Heating of wood under vacuum condition (Absence of Oxygen)
Even if we try to heat wood in the absence of oxygen, we cannot melt wood. In this process first, the water and volatile substances will evaporate and the long-chain molecules will break into small molecules of methane and organic compounds having carbon and hydrogen. Therefore, even in vacuum conditions wood will go through the irreversible process of breaking down into smaller molecules before it can melt.
Here is an interesting video in which various experiments are conducted on wood to check if they can melt under different conditions