What characteristics of the wave define why it is found within this area of the spectrum?

Which of the following observations indicates that there is a small, dense, positively charged part in the center of an atom? some uncharged particles are scattered by a gold foil. all uncharged particles are attracted towards a gold foil. all positively charged particles pass straight through a gold foil. some positively charged particles bounce back from a gold foil.

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

Achemical reaction is done in the setup shown, resulting in a change of mass. what will happen if the same reaction is done in a sealed container that is placed on the electronic balance?