Students will be able to develop and explain a particle-level model to describe their observations of water dissolving salt, the water evaporating, and the salt crystals re-forming. Dissolving a solid ...

As the attractions from the water molecules and their motion pulls the ions apart, the sodium chloride crystal dissolves. The positive areas of the water molecules surround the negative Chloride ions.

Heat can help some substances dissolve faster in water. Salt, for example, will dissolve quicker in hot water than in cold water. When a substance dissolves, it might look like it has disappeared ...