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Question
Mention briefly the salient features of Dalton’s atomic theory (five points)
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Solution
Salient features of Dalton’s atomic theory:
- Matter consists of very small and indivisible particles called atoms, which can neither be created nor can be destroyed.
- The atoms of an element are alike in all respects i.e. size, mass, density, chemical properties but they differ from the atoms of other elements.
- Atoms of an element combine in small numbers to form molecules of the element.
- Atoms of one element combine with atoms of another element in simple whole number ratio to form molecules of compounds.
- Atoms are the smallest units of matter that can take part in a chemical reaction during which only rearrangement of atoms takes place
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