Conc. vs Time Graph for Second Order Reaction

From my understanding plotting the conc. over time for a 0-order reaction yield a negative linear slope. Plotting conc vs time for a first order reaction intuitively yields an exponential type slope. however, my teacher never covered the looks of a conc vs time graph for a second order reaction. What may this look like. In conjunction, what does it look like when we graph its rate over concentration? 




Let's take a single-component second-order reaction:


$$\ce{2A -> B}$$


If it is a 2nd-order reaction, the rate will be proportional to the concentration of $A$, squared:


$$\frac{dA}{dt} = -kA^2$$


That equation can be integrated:


$$\frac{dA}{A^2} == -k dt$$


$$-(A^{-1}-A\_0^{-1}) = -k(t-t\_0)$$


And solving for $A$:


$$A = \frac{1}{k(t-t\_0) + A\_0^{-1}}$$


That is the equation of a hyberbola. It goes to zero *more* slowly than a the expression for a first-order reaction, i.e. an exponential decay. This makes sense because as $A$ gets more and more diluted as the reaction occurs, collisions between $A$ molecules become rarer and rarer.


See [this web page](http://chemwiki.ucdavis.edu/Physical_Chemistry/Kinetics/Reaction_Rates/Second-Order_Reactions) for more information.


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