A-level Chemistry/OCR (Salters)/Kinetics

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Rate equations[edit]

 \mbox{rate} = k[A]^m[B]^n \,\!

 \mbox{order of reaction} = m + n \,\!

Arrhenius equation[edit]

 k = Ae^{-\frac{E_a}{RT}}

Arrhenius plot[edit]

 \ln{(k)} = \ln{ \left ( Ae^{-\frac{E_a}{RT}} \right ) }


 \ln{(k)} = \ln{(A)} + \ln{ \left ( e^{-\frac{E_a}{RT}} \right ) }


 \ln{(k)} = \ln{(A)} + -\frac{E_a}{RT}


 \ln{(k)} = \ln{(A)} - \frac{E_a}{RT}


 \ln{(k)} = - \frac{E_a}{RT} + \ln{(A)}


 \ln{(k)} = - \frac{E_a}{R} \frac{1}{T} + \ln{(A)}


 \mbox{straight-line graphs are always of the form } y = mx + c \,\!


 \mbox{therefore, the dependent variable } y \mbox{ is } \ln{(k)} \,\!


 \mbox{the gradient } m \mbox{ is }  - \frac{E_a}{R} \,\!


 \mbox{the independent variable } x \mbox{ is } \frac{1}{T}  \,\!


 \mbox{the y-intercept } c \mbox{ is } \ln{(A)} \,\!