- chemistry textbooks, paper, pencil.
Look in the school textbook on chemistry eighth or ninth grade, opening it to the section of the rate of chemical reactions.In order to understand how this can affect the speed, you need to determine for yourself the very notion of speed in this context.Thus, the rate of chemical reaction is determined by the change amount of the substance involved in it, or to change the product of any reaction, calculated per unit of time and per unit volume.This definition corresponds to a homogeneous reaction.In the case of a heterogeneous reaction calculation performed on the interface unit.
Please note that the rate of the chemical reaction is the average and instantaneous.Accordingly, it is possible to affect both the one and the other speed.
Note also that the rate of chemical reaction depends on the nature of the reactants.However, the main factors influencing the rate of chemical reaction is the change in temperature, the presence of catalysts and changing the concentration of the reactants.
Pay attention to the mechanism of the effect of changes in the concentration of substances in the rate of the chemical reaction.The essence of this effect is that the number of collisions of particles of reacting substances depends on the concentration of the particles.Increasing the number of particles can be increased and the rate of chemical reaction.This dependence is reflected in the law of mass action.
Consider the mechanism of increasing the rate of a chemical reaction by increasing the temperature.The fact that this factor is the most frequently used along with catalysts.Moreover, it can be used for most chemical reactions.The effect produced by this factor is calculated according to the rule of van't Hoff.This law states that a temperature increase of 10 ° C increases the rate of a chemical reaction in the three or four times.
Do not forget that all of the above listed methods for changing the speed of the chemical reaction does not affect the nature and mechanism of the reaction and do not alter the chemical composition of reagents other than the method of the use of catalysts.Catalysts are also frequently used to improve the speed, though not consumed as a result of the reaction, but are contained in the composition of the reaction intermediates.It is also known that catalysts reduce the overall activation energy of the process that due to the fact that the catalytic process is according to a special way to form the special intermediate species.