chemical reactions and collision theory

• reactants must interact with one another before any reaction can occur.
• if reactants must collide to react, then the frequency of collisions would affect how quickly the reactants form the product.
• increasing the temp would increase how quickly molecules A and B are moving in the container and would thereby increase the chances of the two reactants colliding.
• if the reactants collide more frequently then they form product more freqauently and the reaction rate is increased
• increasing the size of the reactants would increase the likelihood of collision, and therefore the frequency of collision would increase and so would the reaction rate
• increasing the concentration of the reactants would increase the number of particles that could collide and form product.
• with more reactants colliding and forming product, the reaction rate increases.
• Colliding particles must possess a certain minimum amount of energy, called the activation energy, if a collision is to be effective (that is, result in a reaction).
• When two reactant particles collide they do not always result in the formation of product. Sometimes, they rebound unchanged.
• The collision theory states that in order for a reaction to occur, particles must collide with a certain minimum energy. That is the kinetic energies of the colliding particles must add to a certain minimum value.
• The activation energy is the minimum combined kinetic energy that reactant particles must possess in order for their collision to result in a reaction.
• Increasing the temperature of the reactants has two effects:

  1. It increases the rate of movement (kinetic energy) of the reactants making collision more likely.
  2. It increases the kinetic energy of the reactants making collisions more likely to be effective (more likely to form product) by overcoming the activation energy.
• increased kinetic energy from increased temperature
• A catalyst is a substance that increases reaction rate without being consumed in the reaction.
• Catalysts increase reaction rates by providing alternate reaction pathways that have lower activation energies than the original, uncatalyzed pathway.
• enzymes are catalysts.
• Enzymes catalyze (speed up) reactions in animals that would not otherwise occur at appreciable rates at normal animal body temperature because the temperature is not enough to overcome the activation energy.
• catalysts decrease the activation energy allowing the reaction to proceed at a lower energy level.
• reactions take place when particles collide with a eratin amount of energy
• effective collision is equal to a reaction
• the higher the temperature the faster the rate of recation.
• temperature is the average kinetic energy of all the molecules
• the smaller the pieces the larger the surface area. this means more collisions and more chances of reaction
• higher concentration more collision
• low concentration results in a few collisions