Is wood rotting because of a chemical change or a physical change?
A chemical change affects a substance's chemical properties.
Understanding the properties of physical and chemical changes is important to determine whether wood burning is a physical or chemical change.
The changes include breaking a glass, melting ice, dissolving sugar in water, and chopping wood.
A chemical change alters the composition of the substance when the two original substances undergo a chemical reaction to become a new substance.
When you burn wood, it mixes with heat and oxygen to make carbon dioxide, water vapour, and ash.
When you chop wood, you make it smaller, but it still has the same properties.
It will be easier to identify the types of changes that occur when you understand the differences between physical and chemical changes.
The easiest way to distinguish between a physical and a chemical change is to understand that the physical change doesn't change the nature of the substance.
You can make a new piece of wood by putting the ashes together.
You need to combine three substances: fuel, oxygen, and heat, with fuel being wood, gas, or oil.
The reactant has energy stored within it's chemical bonds.
When you heat wood, these small molecules are released from the wood's surface as gases, and they produce heat when they react with the oxygen.
As the fire burns the wood releases more molecule that combine with the air and the ashes are left behind.
To raise the temperature of wood to its ignition temperature, you need enough heat.
It causes the wood to release volatile gases, which are compounds of hydrogen, carbon, and oxygen.
You need to heat the wood to 300 degrees to get smoke, but you have to reach 500 degrees for fire.
Carbon dioxide, water vapor, and other compounds are formed when the compounds split apart at this temperature.
The only way to stop this chemical reaction is to reduce the heat or remove the oxygen that is causing the wood to burn.
It is clear that this is a chemical change once you understand the differences.
A chemical change can change the physical properties of a substance.