Answer:
Atoms always have the same characteristic mass and cannot be created or destroyed.
Step-by-step explanation:
Dalton's atomic theory was the very first complete attempt to describe all matter in terms of atoms and their properties. He based his theory on the law of conservation of mass and the law of constant composition.
The first part of the theory states that all matter is made of atoms, which are indivisible. His law which is related to multiple proportions , is part of the basis for modern atomic theory. He has given the following ideas for conservation of mass:
a. All atoms of a given element are identical.
b. The atoms of different elements vary in mass and size.
c. Atoms are indestructible.
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