Stoichiometric equation for the process

This equation means that, when one mole of R disappears, (Vr/Vr) moles of P appear, but also inevitably (v r/Vr) moles of co-product CP appear and (v r/Vr) moles of the co-reactant CR disappear. 

The by-products BP need not appear in the stoichiometric equation (23), since they are formed in very much lower quantities than the product and the co-product. Besides, for a totally selective process, no by-products are formed. The amounts of by-products formed depend on the way in which the reaction is carried out, whereas the ratio F p/Fp depends only on the stoichiometric equation (23) and is equal to (v p/Vp). 

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