Three groups of drugs are used to reduce the stickiness of platelets, thus preventing platelets from clumping together to form platelet plugs. The anti-platelet drugs are most effective in preventing abnormal blood clots from forming in arteries (as opposed to veins). Aspirin and dipyridamoleâ (Aggrenox).
In order to react, colliding molecules must have a total kinetic energy equal to or greater than some minimum value [Figure 14.13(b)]. The minimum energy required to initiate a chemical reaction is called the activation energy, Ea. The value of Ea varies from reaction to reaction.
No matter how exergonic (reactions that proceed with the release of energy) the overall reaction may be, some energy must be added initially to break the necessary bonds and get the reaction started. The energy level that the reactant molecules must overcome before a reaction can occur is the energy of activation (Ea). The activation energy is the minimum amount of energy required to initiate a chemical reaction. Activation Energy Formula is given below.