Intermediate Topic 704 of 1102 Inorganic Chemistry
Chlorophyll
A magnesium porphyrin complex that absorbs light for photosynthesis.
In-depth explanation of Chlorophyll
Chlorophyll is a magnesium complex of a chlorin ring, a reduced porphyrin, with a long phytol chain that anchors it in the thylakoid membrane. Chlorophyll a and b absorb strongly in the blue and red regions, with peaks near 430 nm and 660 nm, and they reflect green light, which is why leaves are green. The absorbed light energy excites electrons that pass along the photosynthetic electron transport chain to make ATP and NADPH. The central Mg2+ ion stabilizes the ring and helps capture light energy. In autumn chlorophyll breaks down, revealing carotenoids.
Going deeper: Chlorophyll
Key ideas: Mg2+ at the center of a chlorin ring (a reduced porphyrin), with a long phytol tail anchoring it in the membrane. Chlorophyll a absorbs red near 430 and 662 nm and blue light, reflecting green. Light absorption excites an electron, starting photosynthesis: 6CO2 + 6H2O gives C6H12O6 + 6O2, delta G about +2870 kJ per mol of glucose. Mg is bound by four N atoms and can be replaced by H under acid, giving pheophytin with olive color.
Common mistakes and connections: Students think chlorophyll has iron like heme; it has magnesium. Plants look green because green light is reflected, not absorbed. Water, not CO2, is the oxygen source in photosynthesis. Accessory pigments (carotenoids) widen the absorption range. Links to colored complexes, photochemistry, magnesium chemistry and porphyrins.
Visualization of Chlorophyll
Chlorophyll a absorbs strongly in the blue (about 430 nm) and red (about 662 nm), reflecting green; Mg2+ sits at the ring centre. The interactive lesson shows this as a live animation or chart.
Worked example and use case
Leaves look green because chlorophyll absorbs red and blue light and reflects green.
Frequently asked questions about Chlorophyll
What is Chlorophyll?
A magnesium porphyrin complex that absorbs light for photosynthesis.
Is Chlorophyll a beginner, intermediate or advanced topic?
Chlorophyll is a intermediate topic in Inorganic Chemistry. It builds on the vocabulary of beginner topics in this area.
What should I learn before Chlorophyll?
Study these earlier topics in Inorganic Chemistry first: Wilkinson's Catalyst, Bioinorganic Chemistry, Hemoglobin.
What comes after Chlorophyll?
The next topics in Inorganic Chemistry are Cisplatin and Qualitative Analysis of Cations.
Can I practise Chlorophyll with quizzes?
Yes. The interactive lesson includes a self-check question on Chlorophyll, and the Inorganic Chemistry quiz draws on every topic in this area.
Where Chlorophyll fits in Inorganic Chemistry
Chlorophyll is topic 89 of 113 in Inorganic Chemistry.