Question

You are given two sample tubes, each containing a white powder: your task is to determine if these powders are pure substances and two samples of same substance. briefly describe your strategy for completing your task.

Answer 1

Take a bit of each other and burn it individually. If they make the same reaction, they are the same.
Next, take a bit of each other and put it into the water and stir it until it dissolves, then filter those dilutions. If there's something left, the substances are not clean.