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Question
How does the Modern atomic theory contradict and correlate with Dalton's atomic theory?
Solution
Contradictions with Modern atomic theory:
Dalton's atomic theory | Modern atomic theory | ||
(i) | Atoms are indivisible particles. | (i) | Atoms are divisible into sub-atomic particles like protons, electrons and neutrons. |
(ii) | Atoms can neither be created nor destroyed. | (ii) | Atoms can be created and destroyed by nuclear fusion and fission. |
(iii) | The atoms of an element are alike in all respects, but they differ from the atoms of other elements. | (iii) | The atoms of an element may not be alike in all respects, as is seen in the case of isotopes. |
(iv) | Atoms of elements combine in small whole numbers to form molecules. | (iv) | In the formation of organic compounds, the numbers can be very big such as thousands. |
Correlation with Modern atomic theory:
However, modern atomic theory correlates with Dalton's atomic theory in that atoms are the smallest unit of matter involved in a chemical reaction, and the relative number and type of atoms in a particular molecule are constant.
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