Activation energy is the minimum amount of energy required to start or initiate a chemical reaction.
More is the activation energy more difficult is it for the reactants to participate in reaction.
Whereas a catalyst helps in increasing the rate of a reaction by increasing the energy of reactant molecules so that they can cross the activation energy barrier and therefore, formation of products become faster.
Thus, we can conclude that activation energy affect a chemical reaction as it determines how difficult it is to start the reaction.
Enzymes affect the rate of the reaction in both the forward and reverse directions; the reaction proceeds faster because less energy is required for molecules to react when they collide. Thus, the rate constant (k) increases. Figure 3: Lowering the Activation Energy of a Reaction by a Catalyst.
Yes it is a scientific model because it is an outlook of a winter outlook and winter is a season and a type of weather and weather is meteorology and meteorology is a type of science so yes it is a scientific model.
Figure 13.3 (a) Hydra reproduce asexually through budding: a bud forms on the tubular body of an adult hydra, develops a mouth and tentacles, and then detaches from its parent. The new hydra is fully developed and will find its own location for attachment.