Introduction
The cooking of rice is an example of an irreversible and endothermic change. When rice is cooked, it undergoes a chemical reaction that results in irreversible changes to its physical and chemical properties. Additionally, the process of cooking rice requires the absorption of heat energy from an external source, making it an endothermic change.

Irreversible Change
1. Definition: An irreversible change refers to a change that cannot be reversed or undone. It involves the formation of new substances with different properties.
2. Explanation: When rice is cooked, it absorbs water and undergoes a chemical reaction that alters its composition. The starch present in the rice grains absorbs water, swells up, and becomes gelatinized. This irreversible change results in a softer texture and different taste compared to uncooked rice.
3. Example: Other examples of irreversible changes include burning wood, rusting of iron, and baking a cake. In each of these cases, the original substances are transformed into new substances that cannot be easily reversed.

Endothermic Change
1. Definition: An endothermic change is a process that absorbs heat energy from the surroundings.
2. Explanation: Cooking rice requires the application of heat energy to the rice and water mixture. This heat energy is absorbed by the rice grains, causing them to heat up and undergo the cooking process. The absorption of heat is necessary to break down the starch molecules and allow them to absorb water, resulting in the softening and cooking of the rice.
3. Example: Other examples of endothermic changes include melting ice, evaporating water, and photosynthesis. These processes all require the input of heat energy to proceed.

Conclusion
The cooking of rice is an example of an irreversible and endothermic change. The process involves the irreversible transformation of rice grains through the absorption of heat energy. Understanding these concepts helps us appreciate the chemical and physical changes that occur during cooking and the role of energy transfer in these processes.

Because,. it can't be reversed and it used heat energy during reaction