A-level Chemistry/OCR (Salters)/Kinetics

Rate equations

$\text{rate}=k[A{]}^m[B{]}^n$

$\text{order of reaction}=m+n$

Arrhenius equation

$k=A{e}^{-\frac{E_a}{RT}}$

Arrhenius plot

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

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

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

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

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

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

$\text{straight-line graphs are always of the form }y=mx+c$

$\text{therefore, the dependent variable }y\text{ is }\ln (k)$

$\text{the gradient }m\text{ is }-\frac{E_a}{R}$

$\text{the independent variable }x\text{ is }\frac{1}{T}$

$\text{the y-intercept }c\text{ is }\ln (A)$