Which statements in dalton's original atomic theory are now considered to be incorrect? describe how modern atomic theory differs from theses statements?

Incorrect statement in Dalton's original atomic theory are that atoms are indestructible and statement that all atoms of one element are same mass and characteristics.
Modern atomic theory is, of course, a little bit updated but original Daltons's theory is still remains. By modern atomic theory atoms can be destructed by nuclear reaction, but no with chemical reaction. Also there are different kinds of atoms in one element, their mass can be different. 

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