Option 1: Curdling of milk - Curdling of milk is a chemical change. It occurs when milk turns into curd due to the action of bacteria or enzymes. This change involves a chemical reaction that transforms the proteins present in milk.

Option 2: Ripening of fruit - Ripening of fruit is also a chemical change. It involves various biochemical processes such as the breakdown of starches into sugars and the production of ethylene gas. These changes lead to the softening, sweetening, and change in color of fruits.

Option 3: Evaporation of water - This option is correct. Evaporation of water is not a chemical change but a physical change. It is the process by which water molecules escape from the liquid phase into the gaseous phase without any chemical reaction taking place.

Option 4: Burning of coal - Burning of coal is a chemical change. It involves the combustion of coal with oxygen, resulting in the release of heat, light, and the formation of carbon dioxide and other combustion products.

In summary, the correct answer is option 3 because the evaporation of water is a physical change, not a chemical change.