Now let's move on to the double displacement reaction, also sometimes known as a ping pong reaction. So what exactly is the major difference between the sequential reaction and the double displacement reaction? Well, just like the sequential reaction, this is the equation that generalizes the double displacement reaction. But unlike in the sequential case in which these two molecules, A and B, have to bind into the active side together for that reaction to take place, in this particular case, in a double displacement reaction, what happens is first, one of these molecules, let's say A binds onto the active side of that enzyme and a group on A is transferred into that enzymes active side and that modifies that enzyme and it also transforms our reactant A into, let's say product C. And then product C is released. And once product C is released, we now have that modified enzyme. And only now can the second substrate B actually bind onto the active site of that modified enzyme to form an intermediate between the enzyme and that reactant B.