Because the leaf is not burning.
It is a chemical change, a degradation of the compounds from the leaf.
Chemical
The change is leaf color is a chemical change.
chemical
Crushing a leaf is a physical change, not a chemical change because the chemical composition of the leaf remains the same before and after crushing. However, if the crushing process causes the leaf to release certain chemicals due to breaking of cell walls, then it can result in a chemical change.
The decay of organic matter such as leaves is a chemical change.
Chemical. It has to do with the closing of the part that connects the leaf to the tree and the lack of nutrients causes the leaf to turn colours.
The color change, though physical by itself, is caused by a chemical change of some colored substances in cabbage.
The color change in a leaf typically indicates a chemical change when it results from the breakdown of chlorophyll and the revealing of other pigments, such as carotenoids and anthocyanins, as the plant prepares for winter. This process involves biochemical reactions that alter the pigments present in the leaf. Conversely, a physical change may be indicated if the color change is due to external factors like exposure to light or temperature without altering the leaf's chemical composition.
Photosynthesis makes a leaf green so when it turns brown it has stopped doing photosynthesis so most likely it is chemical change. Helpful enough? :|
chemical
It depends. In most cases, it is a chemical change as the different colored species have different chemical structures. However, it is possible to change color by very finely dividing particles of matter and this is a physical change.