View archive. The Selma Fire Department was established in 1974, âto protect and enhance the quality of life in Selma through a program of services directed toward public education, prevention, and control in areas of fire, rescue, medical, emergencies, hazardous materials incidents, and disasters.â.
2016-09-05T14:42:37-04:00. Collision theory is the topic among the choices given in the question that is used to explain activation energy and how chemical reactions happen. The correct option among all the options that are given in the question is the second option or option B. I hope that the answer has come to your help.
Most chemical reactions involve the breaking and formation of chemical bonds. It takes energy to break a chemical bond but energy is released when chemical bonds are formed. If more energy is released than consumed, then the chemical reaction evolves heat and is said to be exothermic. On the other hand if the reaction consumes more energy than it releases then the reaction absorbs heat and is said to be endothermic. Most reactions are exothermic. The amount of heat generated by a reaction can be quantified. The quantity that specifies the amount of heat is known as the enthalpy . If is positive then the reaction is endothermic and if it is negative the reaction is exothermic.