Look at the descriptions of a chemical change. Then select the correct sign of the chemical change.

Question

[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.