In chemistry we used different chemicals to determine the properties of several substances. We could not tell the difference with any great accuracy between the powders in the lab on sight alone, so we had to resort to using the reactions of the chemicals to the powders, the iodine changed color with the cornstarch and baking powder, not quite mixing with the cornstarch, while it simply absorbed the baking soda. The water fizzed slightly with the baking power, absorbed the baking soda and did’t mix with the cornstarch. The vinegar fizzed dramatically with baking soda, fizzed slightly with baking powder and didn’t mix with the cornstarch. Given an unknown white powder, based on the reactions observed in the lab, it would be possible to identify the substance by comparing it’s reactions to chemicals with reactions of known chemicals. This could be used to identify substances to solve crimes, or ID parts of a substance.