Rate Equations Flashcards
what is the definition of rate of reaction?
Change in Concentration/Time
what does zero order mean?
as the concentration changes the rate remains the same
what does first order mean?
as the concentration changes by a factor , the rate changes by that same factor
what does second order mean?
as the concentration changes by a factor the rate changes by that factor squared
what does a rate concentration graph look like if the rate is zero order?
straight horizontal line
what does a concentration time graph look like if the rate is zero order?
straight diagonal line with negative constant gradient
what does a rate concentration graph look like if the rate is first order?
a straight diagonal line
what does a concentration time graph look like if the rate is first order?
a curve with a negative gradient
what does a rate concentration graph look like if the rate is second order?
an exponential shaped graph
what does a concentration time graph look like if the rate is second order?
a curve with a negative gradient
how to calculate K from concentration-time graph?
K is the gradient of a concentration-time graph
how to determine whether an order is first or second using a concentration-time graph
- calculate the gradient at two different points on the graph
- if the change in concentration is the same as the change in gradient then it is first order
- if the change in concentration is equal to the change in gradient squared then it is second order
what does the term rate constant (K) mean?
the constant relating the rate of the reaction to the concentrations of reactants at a particular temperature
how does K (rate constant) vary with temperature?
as the temperature increases , K also increases
why does K (rate constant) vary with temperature?
as the temperature increases the rate of reaction increases. the faster the rate of reaction the larger the K value
