What is photosynthesis? Write the reaction …

When a new substance is formed after the change, it is called chemical change. Chemical changes cannot be reversed by simple physical means. Many chemical changes are irreversible. Examples: Burning of candle, rusting of iron, charcoal burns, molecules of oxygen from the air bond with the carbon in the coal etc.
103) Plants do need food for their survival and they would not wait or depend on others to provide them food. There is a particular mechanism in plants with which they prepare their food. This mechanism is known as Photosynthesis. Photosynthesis is a biological process used by plants to prepare their food with the help of sunlight and energy.
The overall reaction of photosynthesis process is:
6CO₂ +  6H₂O  → C₆H₁₂O₆  + 6O₂
6 molecules of Carbon dioxide + 6 molecules of  Water produce 1 molecule of   Glucose + 6 molecules of Oxygen