Answer: This unknown powder is most likely made up of ionic bond.
Step-by-step explanation:
An ionic compound is defined as the compound formed due to transfer of electrons between its atoms.
As we know that like dissolves like. Therefore, an ionic compound is readily soluble in a polar solvent like water.
Hence, when an unknown white powder is added to a beaker of water and stirred. The powder disappears after a few seconds because the white powder is ionic in nature and it is made up of ionic bond.