1. which of the following is not part of john dalton's atomic theory?
a. all elements are composed of atoms.
b. all atoms of the same element have the same mass.
c. atoms contain subatomic particles.
d. a compound contains atoms of more more than one element.
2. who provided evidence for the existence of a nucleus in an atom?
a. john dalton
b. j. j thomson
c. democritus
d. ernest rutherford