I have to calculate the exact composition in grams of a blend of two chemicals which react each other by a redox reaction.
The question is: giving that 1 molecule of product A reacts with 1 molecule of product B and that the molecular weight of A is 400 and of B is 600, can I use a ratio 4/6 between the two chemicals (for instance to use 400 g of A and 600 g of B)? 

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