Which property would determine if a substance is acidic?

This classification of drug typically changes the brain's chemistry and reduces its ability to create its own endorphins.

Ascientist is measuring the pressure that is exerted by each of the following gases in the atmosphere: carbon dioxide, oxygen, and nitrogen. which term most likely describes what she is measuring?

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?