Reaction rates refer to the speed at which a chemical reaction occurs. This can be measured by observing how quickly reactants are converted into products. Factors that influence reaction rates include temperature, concentration of reactants, surface area, and the presence of catalysts. For example, increasing the temperature usually speeds up reactions because particles move faster and collide more often. Understanding reaction rates is important in various fields, such as chemistry, pharmaceuticals, and environmental science. In pharmaceuticals, knowing how quickly a drug reacts in the body can help determine its effectiveness. In environmental science, reaction rates can influence how pollutants break down in the environment.