chapter 6 Flashcards
what is rate?
the speed at which reactants are used up or products are formed
what is rate of reaction?
change in concentration of reactants or products per unit time
how do you calculate average rate?
average rate = concentration / time
what is collision theory?
a reaction can only occur when particles collide in the correct orientation with E > Ea
what conditions must be fulfilled for a successful collision?
more than a minimum amount of energy, collide with correct orientations
what factors affect reaction rate?
concentration, pressure, surface area, temperature, catalyst
what is the effect of concentration of ROR?
more particles in a certain volume, particles collide more often and therefore there is a greater chance of a successful collision occurring in a certain time
what is the effect of pressure on ROR?
same as increasing concentration
what is the effect of surface area on ROR?
more particles exposed so more increase in concentration and increasing the reactant collisions
what is the effect of temperature on ROR?
temperature increases the kinetic energy supplied to the particles which increases the frequency of collisions
what is Maxwell-Boltzmann distribution?
a graph showing the distribution of molecular kinetic energies in a sample of gas at a particular temperature
what is a catalyst?
a substance that increases the rate of a chemical reaction without being used up in the reaction?
what is activation energy?
minimum energy that colliding molecules need in order to have successful collisions leading to a reaction
how does a catalyst work?
allowing the reaction to proceed by an alternative pathway of lower activation energy
