Definitions of Reaction Rate

We define the rate of reaction verbally for a species involved in a reacting system either as a reactant or as a product. The system may be single-phase or multiphase, may have fixed density or variable density as reaction proceeds, and may have uniform or varying properties (e.g., p, CA, T, P) with respect to position at any given time. The extensive rate of reaction with respect to a species A, RA, is the observed rate of formation of A  

The intensive rate of reaction, rA, is the rate referred to (.NQ), or rate basis, such as volume of reacting system a specified normalizing or mass of catalyst quantity 

The rate, RA or rA, as defined is negative if A is consumed, and is positive if A is produced. One may also define a species-independent rate of reaction for a single reaction or step in a mechanism, but this requires further consideration of stoichiometry 

The rate rA is independent of the size of the reacting system and of the physical circumstances of the system, whereas RA is not. Thus, rA may be considered to be the 

The operational interpretation of rA, as opposed to this verbal definition, does depend on the circumstances of the reaction.1 This is considered further in Chapter 2 as a consequence of the application of the conservation of mass to particular situations. Furthermore, rA depends on several parameters, and these are considered in Section 1.4.2. The rate with respect to any other species involved in the reacting system may be related to rA directly through reaction stoichiometry for a simple, single-phase system, or it may require additional kinetics information for a complex system. This aspect is considered in Section 1.4.4, following a preliminary discussion of the measurement of rate of reaction in Section 1.4.3. 

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What is the distinction between the time variable employed in the rate-of-reaction definition and that pertaining to the time of operation of a process in which a chemical reaction occurs ... 

Based on the basis and the rate of reaction definition in mass balance, r = 100 mol/min. Take the reference temperature as 200°C thus, we get... 

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