Asubstance that forms when two or more elements join chemically is a. an ion b. compound c. a formula d. an atom

When two or more elements join together chemically, we have a B. compound.

Water is a compound because of its molecular formula H2O

There are 2 atoms of hydrogen and 1 atom of oxygen bonded together.

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.