If you have a white powder that could be either Epsom salt or table how can decide which one it is?

Taste test: Both Epsom salt (magnesium sulfate) and table salt (sodium chloride) are soluble in water. Taste a very small amount of the powder dissolved in water. Epsom salt has a bitter taste, while table salt has a salty taste.

Smell test: Epsom salt has a faint odor of sulfur, while table salt is generally odorless.

Chemical test:

1) Add a few drops of vinegar to the powder. If it is table salt, it will fizz. If it is Epsom salt, there will be no reaction.

2) Mix a small amount of the powder with water and test the solution with a pH strip. Epsom salt is slightly acidic and will have a pH below 7, while table salt is neutral and will have a pH of around 7.