How does Dalton’s atomic theory account for the fact that when 1.000 g of water is decomposed into its elements, 0.111 g of hydrogen and 0.889 g of oxygen are obtained regardless of the source of water?

Question

anonymous · Answer

1 g of water is 1/18th of a mole of water, regardless of the source. 

The stoichiometry of the reaction" H2O -> H2 + 1/2 O2 indicates that 1/18th of a mole of H2 is formed, which is 0.111 g, 1/36 a mole of of O2, which is 0.889 grms of O2 is formed.
 Dalton's law indicates that the molar equation can be expressed with whole numbers (multiply above by 2 to get such an equation).