🌿 Photosynthesis
Synthesis
6CO₂ + 6H₂O + light
→ C₆H₁₂O₆ + 6O₂
Plants convert carbon dioxide and water into glucose (sugar) using sunlight. This is the foundation of almost all food on Earth.
→ Every breath of oxygen you take came from this reaction
🏃 Cellular Respiration
Combustion
C₆H₁₂O₆ + 6O₂
→ 6CO₂ + 6H₂O + ATP
The reverse of photosynthesis — cells break down glucose with oxygen to release energy (ATP) for all bodily functions.
→ Happens in every cell of your body right now
🔥 Burning Methane
Combustion
Natural gas (methane) burns completely in oxygen, releasing heat and light. Used in cookers, boilers, and power stations worldwide.
→ One of the cleanest-burning fossil fuels
🌊 Electrolysis of Water
Decomposition
Passing electricity through water splits it into hydrogen and oxygen gas. Used to produce green hydrogen fuel from renewable energy.
→ The future of clean energy storage
🦷 Rusting Iron
Synthesis / Redox
4Fe + 3O₂ + water
→ 2Fe₂O₃
Iron atoms lose electrons to oxygen in the presence of water. The reddish-brown iron(III) oxide (Fe₂O₃) forms on the surface as rust.
→ Costs the global economy ~$2.5 trillion per year
🧁 Baking Soda + Vinegar
Acid-Base
NaHCO₃ + CH₃COOH
→ CO₂↑ + H₂O + NaCH₃COO
Baking soda (a base) reacts with acetic acid in vinegar. The CO₂ gas produced causes the fizzing. The same reaction leavens cakes and bread.
→ You can try this safely at home right now
💡 Haber Process
Synthesis
Nitrogen and hydrogen react under high pressure and temperature with an iron catalyst to make ammonia — the basis of all synthetic fertilisers.
→ Feeds roughly half of all people alive today
🔋 Zinc-Carbon Battery
Redox
In a battery, zinc is oxidised (loses electrons) at the anode. The electrons flow through the external circuit as electric current, powering devices.
→ The same principle powers lithium-ion phone batteries
