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Valency is the reason for the varying weights of the same element in different compounds. Once you know the valency of all the elements you can work out for yourself the formula for a chemical compound, provided you know its molecular weight, for valency tells you the number of atoms of one element that must combine with one atom of the other, and their total weights must add up to the molecular weight.
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Valency is the reason for the varying weights of the same element _________________.
in different styles
in the same compounds
in different components
in different compounds