a. Because a lawn is watered and fertilized, the grass grows thicker.
b. An overgrown lawn is manicured by mowing it with a lawn mower.
c. Ice cubes form when a tray filled with water is placed in a freezer.
d. An egg is fried in a skillet.
The Correct Answer and Explanation is :
The correct answer here is d. An egg is fried in a skillet.
Explanation:
This sentence demonstrates a chemical change because cooking an egg involves a transformation that cannot be reversed. When you fry an egg in a skillet, heat is applied, which causes proteins in the egg white and yolk to denature and change their structure. These changes are permanent, and the egg cannot return to its raw state. This is an example of a chemical reaction, where new substances (such as the solidified egg white and yolk) are formed through heat and chemical processes.
Here’s an analysis of the other options:
- a. Because a lawn is watered and fertilized, the grass grows thicker.
This is a physical change, not a chemical one. The watering and fertilizing of grass promotes its growth, which is a physical process. There’s no chemical transformation occurring in the grass, just a natural process of cell division and expansion that is influenced by external factors like water and nutrients. - b. An overgrown lawn is manicured by mowing it with a lawn mower.
This is also a physical change. Mowing the lawn does not change the chemical composition of the grass; it simply alters its appearance by cutting it. The grass may look different, but the individual plant cells have not undergone any chemical reactions. - c. Ice cubes form when a tray filled with water is placed in a freezer.
This is a physical change, not a chemical one. When water freezes, it changes from a liquid to a solid state (ice), but the molecular structure of water remains H2O. The process is reversible—when the ice melts, it returns to its liquid form, making it a physical, not a chemical, change.
In conclusion, option d is the only one that involves a chemical change, while the others involve physical changes.