* Physical Change: The most obvious change is the visual shift in color. This is a physical change because it involves a change in the appearance of the leaf without altering its chemical composition at the molecular level.
* Chemical Change: But what causes those visual changes? The chemical composition of the leaf *does* change. Here's a simplified explanation:
* Chlorophyll: The green pigment that dominates leaves during the growing season breaks down as temperatures drop and the amount of sunlight decreases.
* Other Pigments: Other pigments like carotenoids (yellows and oranges) and anthocyanins (reds and purples) were already present in the leaf but masked by the chlorophyll. When the chlorophyll degrades, these other pigments become visible, resulting in the autumn colors.
In Conclusion: The process of leaves changing color involves both physical changes (the visual shift) and chemical changes (the breakdown of chlorophyll and the unmasking of other pigments).
