KINETICS Flashcards
explain why most collisions do not lead to a reaction
reactions will only occur when collisions will occur with sufficient amount of energy. the energy needed is referred to as the activation energy ( minimum amount of energy). This is the energy needed to break relevant bonds in the reactant molecules.
define activation energy
the minimum amount of energy required for particles to collide
what does the molecular energies gases show
it shows the spread of energies of molecules of gases or liquid at a particular temperature
define rate of reaction
change in concentration of a substance in unit time
how can a rate shown In a gradient
rate is equal to the gradient of the tangent of the curve
what will happen to Maxwell distribution at high temperature
as the temperature increases the distribution shifts towards having more molecules with higher energy, the particles will collide more frequently and have energy greater than the activation energy so more collisions are a result of this
what will happen to Maxwell distribution at low temperature
at lower temperature, the energy of particles will have more energy than the activation energy so more successful collisions will occur
how does a change in concentration/ pressure influence the rate of reaction
at a higher concentration there are more particles per unit volumes and so the particles collide at a greater frequency so there will be a higher frequency ion successful collisions. There is a higher rate of reaction and so at high concentration the shape of energy distribution on the curve will be greater due to more particles being present.
define catalyst
increases the rate of reaction without getting used up, this is done by providing an alternative reaction with a lower activation energy. at lower activation energy the particles will have energy greater than the activation energy so there will be more collisions and faster reaction.
