Here is the completed experiment.
Based on the information provided, the mineral that will dissolve easily in water is rock salt. This is because rock salt is composed of the mineral halite, which is highly soluble in water. Chalk, on the other hand, is composed of the mineral calcite, which is only slightly soluble in water. Talcum powder is composed of the mineral talc, which is insoluble in water.
Here's a summary of the solubility of the three minerals in water:
Rock salt (halite): Highly soluble
Chalk (calcite): Slightly soluble
Talcum powder (talc): Insoluble
To test the solubility of the minerals, you can follow these steps:
Fill a clear plastic cup with water.
Add a small amount of each mineral to the cup of water.
Stir the water with a spoon.
Observe which minerals dissolve in the water.
You should find that the rock salt dissolves quickly and completely in the water. The chalk will dissolve slightly, but you will still be able to see some of the chalk particles in the water. The talcum powder will not dissolve at all in the water.