Photosynthesis

6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

Overview

The most important photochemical reaction on Earth. Plants, algae, and cyanobacteria use chlorophyll to capture sunlight and convert carbon dioxide and water into glucose and oxygen. The light reactions split water at photosystem II, while the Calvin cycle fixes CO₂. This reaction produces virtually all atmospheric oxygen and is the foundation of most food chains.

Participants

Role	Substance	Coefficient	State
Reactant	Carbon Dioxide CO₂	6	(g)
Reactant	Water H₂O	6	(l)
Product	Glucose C₆H₁₂O₆	1	(s)

Everyday Example

Every bite of food you eat and every breath of oxygen you inhale ultimately traces back to photosynthesis.

Industrial Importance

Photosynthesis fixes about 120 billion tonnes of carbon annually. Artificial photosynthesis research aims to produce clean fuels from sunlight.

Properties

Type: Photochemical
Reversible: No
Energy: Endothermic
ΔH: 2803.0 kJ/mol
Catalyst: Chlorophyll

Related Reactions

Chlorophyll Fluorescence Cis-Trans Isomerization of Retinal Dye-Sensitized Solar Cell (Grätzel Cell) Firefly Bioluminescence (Luciferin Oxidation) Luminol Chemiluminescence Ozone Decomposition by UV Ozone Formation by UV Light Photocatalytic NOx Removal Photocatalytic Water Splitting (TiO₂) Photochemical Cycloaddition ([2+2])

Frequently Asked Questions

What is the equation for Photosynthesis?

The balanced equation is: 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂.

What type of reaction is Photosynthesis?

Photosynthesis is a photochemical reaction.

Is Photosynthesis exothermic or endothermic?

Photosynthesis is endothermic (absorbs energy). The enthalpy change (ΔH) is 2803.0 kJ/mol.

What conditions are needed for Photosynthesis?

This reaction requires a catalyst (Chlorophyll).