Why is the rate of reaction expressed as negative with respect to a reactant? Is the rate of reaction really negative?
(N/A) The rate of reaction is defined as the change in concentration of a reactant or product per unit time. For a reactant $R$ converting to product $P$,the rate is given by: $Rate = -\frac{d[R]}{dt} = \frac{d[P]}{dt}$.
Since the concentration of a reactant decreases over time,the change in concentration,$d[R]$,is negative. To ensure that the rate of reaction is always a positive quantity,a negative sign is introduced in the expression for the reactant.
The rate of reaction itself is never negative; it is a measure of the speed of the reaction,which is always a positive value.
Since the concentration of a reactant decreases over time,the change in concentration,$d[R]$,is negative. To ensure that the rate of reaction is always a positive quantity,a negative sign is introduced in the expression for the reactant.
The rate of reaction itself is never negative; it is a measure of the speed of the reaction,which is always a positive value.
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