Answer to Question #86736 in General Chemistry for Grace

Question

Modern atomic theory changes which two pieces from Daltons theory?

Answer 1

1.In Dalton's theory atoms were considered as not divisible further. But now it is proved that atom can be divided in further parts -Electron , Proton , Neutron 

2.Again according to Dalton's theory atoms from same element have same weight. But after discovery of isotope It is confirmed that atom from same element have different weight.

these two changes are in Modern atomic theory.