#CHEMISTRY

#ATOMS

#PERIODICTABLE

Physical Change

Example :

• Melting of Ice :

• Initial state: Ice (solid)

• Process: When ice is heated, it absorbs energy and its molecules gain kinetic energy, overcoming the intermolecular forces holding them together in a fixed position.

• Final state: Liquid water (liquid)

• Observable change: The ice changes its state from solid to liquid, but its chemical composition remains the same. Water molecules are still made up of hydrogen and oxygen atoms.

Chemical Change

Example :

• Burning of Wood:

• Initial state: Wood (organic material)

• Process: When wood is exposed to a flame or heat source, it undergoes a combustion reaction with oxygen in the air. The chemical bonds in the wood are broken, and new substances, such as carbon dioxide (CO₂) and water (H₂O), are formed.

• Final state: Ash, smoke, and gases (carbon dioxide, water vapor, etc.)

• Observable change: The wood is transformed into entirely new substances with different properties. The original wood cannot be recovered from the ash and gases.

• In this example, the chemical composition of the wood has changed, indicating a chemical reaction.