How did Dalton Atomic Theory explain the law of definite proportions?
1 Answer
Dalton's atomic theory consisted of several postulates.
Explanation:
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All matter consists of indivisible particles called atoms.
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Atoms of the same element are similar in shape and mass, but differ from the atoms of other elements.
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Atoms cannot be created or destroyed.
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Atoms of different elements may combine with each other in a fixed, simple, whole number ratio to form compound atoms.
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Atoms of same element can combine in more than one ratio to form two or more compounds.
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Atoms are the smallest unit of matter that can take part in a chemical reaction.
The law of definite proportions states that a chemical compound always contains exactly the same proportion of elements by mass.
For example, all samples of the compound carbon monoxide contain 42.88 % carbon and 57.12 % oxygen by mass.
The atomic theory explains the law of definite proportions:
Dalton proposed that the smallest particle of carbon monoxide was a molecule. This molecule consisted of one carbon atom and one oxygen atom.
If all oxygen atoms had a mass about 1.33 times that of carbon atoms, carbon monoxide would have exactly the above composition.
