Question

Look at the descriptions of a chemical change. Then select the correct sign of the chemical change.
[Title] Precipitate formed Color changed Gas released
Energy released
Odor change
Explosion of Dynamite





The clear part of an egg turns white while cooking.





Souring milk





Two liquids are mixed and a solid forms.





A glass of soda produces bubbles and makes a hissing sound.

Answer 1

Based on the descriptions provided, here are the signs of chemical changes associated with each scenario:

1. **Explosion of Dynamite**: This is a chemical change characterized by energy release and possibly the formation of gases, alongside other signs such as sound and light.

2. **The clear part of an egg turns white while cooking**: This indicates a chemical change known as denaturation of proteins, resulting in a color change.

3. **Souring milk**: This is a chemical change caused by bacterial action, leading to odor change and possibly a change in texture (curd formation) as well.

4. **Two liquids are mixed and a solid forms**: This is a chemical change known as precipitation, where a new solid (precipitate) is formed from the reaction of the liquids.

5. **A glass of soda produces bubbles and makes a hissing sound**: The release of gas (carbon dioxide) indicates a chemical change occurring as the pressure is released when opening the soda.

In summary, all of the scenarios described indicate signs of a chemical change.