Determine the best course of action when acid or base is spilled on the skin. Apply base to an acid burn, or acid to a base burn. Remove as much of the acid or base as possible using a towel. None of these actions are appropriate. Rinse the affected area immediately with water.

Awhite powder is added to a solution. the images show observations made before the powder is added, just after the powder has been added, and a little while later. (the liquid in the small beaker is phenol red solution.) what evidence shows that a chemical change has taken place?