Question

A scientist designs some experiments to record how various substances change. She then reviewed her results. Which of the investigations listed below is an example of how the substance changed chemically?

1. Hydrochloric acid is stored inside plastic containers.
2. Sodium metal reacts violently and explodes with water.
3. After heating aluminum in a crucible, it began melting at 1200 degrees F
4. Grinding Copper sulfate allowed it to be dissolved much quicker.

Answer 1

1 Hydrochloric acid is stored inside plastic containers.

Step-by-step explanation:

Hydrochloric acid is a strong acid and is extremely reactive with metals, metal oxides, and skin. Proper storage is critical, because the acid can react with the storage container, and spillage can result in acid burns, particularly if the acid is extremely concentrated. That would be a chemical reaction.