Kinetics Ratio of products in parallel reactions

What parallel reactions are we talking about?

@argentum When one substrate takes part in two reactions. If to turn the process into scheme: A -> B, A -> C

@chaoticgood Yes, there are various methods for changing the direction of reactions - temperature, choice of catalyst and change of reactants. So is the choice of solvent

@argentum So if we need to carry out the reaction in a certain condition (such as solvent and catalyst) in order not to influence the mechanism we can use temperature, right?

@chaoticgood Well, as an option, but it's all very individual to certain reactions often

@chaoticgood I have a lot of questions. You give an example of a solvent and a catalyst? What phase state do you think they should be in?

And how do you want not to change the mechanism by changing only the reaction temperature?

You are talking about such a parameter as temperature. You want, without changing the phase state of the system in which the parallel reaction occurs, to affect it only by temperature. Then what is the catalyst for anyway?

By changing the temperature, it is possible to achieve a change in the reaction mechanism, for example, as in the interaction of propylene with chlorine

@damiryagudin In a certain temperature intervals you can communicate greater amount of energy to the system and not to change the mechanism 

@damiryagudin Adding the catalyst to the system changes the mechanism of the process 

@chaoticgood It is possible, but it is also necessary to take into account the mutual solubility of reagents and solvent from temperature.